Patient interface

ABSTRACT

A patient interface includes a frame assembly (16100) including connectors operatively attachable to headgear, a cushion assembly (16175) including a shell (161800) and a seal-forming structure (16200) structured to form a seal with the patient&#39;s nose and/or mouth, and an air delivery connector (16600). The cushion assembly and air delivery connector are structured to releasably connect to the frame assembly independently of each other. A static face seal and separate static diametric seal between the shell (161800) and frame (16100). A dynamic face seal and separate dynamic diametric seal between the air delivery connector (16600) and frame (16100). Separate claims (FIG. 6) to a frame assembly (16100) with upper headgear connector arms (16134) including at least one slot (6146) (claim 17) or flexible portions (claim 22) to form hinges structured and arranged to conform to varying facial profiles.

1 CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.62/222,593, filed Sep. 23, 2015, and U.S. Provisional Application No.62/376,961, filed Aug. 19, 2016, each of which is incorporated herein byreference in its entirety.

2 BACKGROUND OF THE TECHNOLOGY 2.1 Field of the Technology

The present technology relates to one or more of the detection,diagnosis, treatment, prevention and amelioration of respiratory-relateddisorders. The present technology also relates to medical devices orapparatus, and their use.

2.2 Description of the Related Art 2.2.1 Human Respiratory System andits Disorders

The respiratory system of the body facilitates gas exchange. The noseand mouth form the entrance to the airways of a patient.

The airways include a series of branching tubes, which become narrower,shorter and more numerous as they penetrate deeper into the lung. Theprime function of the lung is gas exchange, allowing oxygen to move fromthe air into the venous blood and carbon dioxide to move out. Thetrachea divides into right and left main bronchi, which further divideeventually into terminal bronchioles. The bronchi make up the conductingairways, and do not take part in gas exchange. Further divisions of theairways lead to the respiratory bronchioles, and eventually to thealveoli. The alveolated region of the lung is where the gas exchangetakes place, and is referred to as the respiratory zone. See“Respiratory Physiology”, by John B. West, Lippincott Williams &Wilkins, 9th edition published 2011.

A range of respiratory disorders exist. Certain disorders may becharacterised by particular events, e.g. apneas, hypopneas, andhyperpneas.

Obstructive Sleep Apnea (OSA), a form of Sleep Disordered Breathing(SDB), is characterized by events including occlusion or obstruction ofthe upper air passage during sleep. It results from a combination of anabnormally small upper airway and the normal loss of muscle tone in theregion of the tongue, soft palate and posterior oropharyngeal wallduring sleep. The condition causes the affected patient to stopbreathing for periods typically of 30 to 120 seconds in duration,sometimes 200 to 300 times per night. It often causes excessive daytimesomnolence, and it may cause cardiovascular disease and brain damage.The syndrome is a common disorder, particularly in middle agedoverweight males, although a person affected may have no awareness ofthe problem. See U.S. Pat. No. 4,944,310 (Sullivan).

Cheyne-Stokes Respiration (CSR) is another form of sleep disorderedbreathing. CSR is a disorder of a patient's respiratory controller inwhich there are rhythmic alternating periods of waxing and waningventilation known as CSR cycles. CSR is characterised by repetitivede-oxygenation and re-oxygenation of the arterial blood. It is possiblethat CSR is harmful because of the repetitive hypoxia. In some patientsCSR is associated with repetitive arousal from sleep, which causessevere sleep disruption, increased sympathetic activity, and increasedafterload. See U.S. Pat. No. 6,532,959 (Berthon-Jones).

Respiratory failure is an umbrella term for respiratory disorders inwhich the lungs are unable to inspire sufficient oxygen or exhalesufficient CO₂ to meet the patient's needs. Respiratory failure mayencompass some or all of the following disorders.

A patient with respiratory insufficiency (a form of respiratory failure)may experience abnormal shortness of breath on exercise.

Obesity Hyperventilation Syndrome (OHS) is defined as the combination ofsevere obesity and awake chronic hypercapnia, in the absence of otherknown causes for hypoventilation. Symptoms include dyspnea, morningheadache and excessive daytime sleepiness.

Chronic Obstructive Pulmonary Disease (COPD) encompasses any of a groupof lower airway diseases that have certain characteristics in common.These include increased resistance to air movement, extended expiratoryphase of respiration, and loss of the normal elasticity of the lung.Examples of COPD are emphysema and chronic bronchitis. COPD is caused bychronic tobacco smoking (primary risk factor), occupational exposures,air pollution and genetic factors. Symptoms include: dyspnea onexertion, chronic cough and sputum production.

Neuromuscular Disease (NMD) is a broad term that encompasses manydiseases and ailments that impair the functioning of the muscles eitherdirectly via intrinsic muscle pathology, or indirectly via nervepathology. Some NMD patients are characterised by progressive muscularimpairment leading to loss of ambulation, being wheelchair-bound,swallowing difficulties, respiratory muscle weakness and, eventually,death from respiratory failure. Neuromuscular disorders can be dividedinto rapidly progressive and slowly progressive: (i) Rapidly progressivedisorders: Characterised by muscle impairment that worsens over monthsand results in death within a few years (e.g. Amyotrophic lateralsclerosis (ALS) and Duchenne muscular dystrophy (DMD) in teenagers);(ii) Variable or slowly progressive disorders: Characterised by muscleimpairment that worsens over years and only mildly reduces lifeexpectancy (e.g. Limb girdle, Facioscapulohumeral and Myotonic musculardystrophy). Symptoms of respiratory failure in NMD include: increasinggeneralised weakness, dysphagia, dyspnea on exertion and at rest,fatigue, sleepiness, morning headache, and difficulties withconcentration and mood changes.

Chest wall disorders are a group of thoracic deformities that result ininefficient coupling between the respiratory muscles and the thoraciccage. The disorders are usually characterised by a restrictive defectand share the potential of long term hypercapnic respiratory failure.Scoliosis and/or kyphoscoliosis may cause severe respiratory failure.Symptoms of respiratory failure include: dyspnea on exertion, peripheraloedema, orthopnea, repeated chest infections, morning headaches,fatigue, poor sleep quality and loss of appetite.

A range of therapies have been used to treat or ameliorate suchconditions. Furthermore, otherwise healthy individuals may takeadvantage of such therapies to prevent respiratory disorders fromarising. However, these have a number of shortcomings.

2.2.2 Therapy

Continuous Positive Airway Pressure (CPAP) therapy has been used totreat Obstructive Sleep Apnea (OSA). The mechanism of action is thatcontinuous positive airway pressure acts as a pneumatic splint and mayprevent upper airway occlusion, such as by pushing the soft palate andtongue forward and away from the posterior oropharyngeal wall. Treatmentof OSA by CPAP therapy may be voluntary, and hence patients may electnot to comply with therapy if they find devices used to provide suchtherapy one or more of: uncomfortable, difficult to use, expensive andaesthetically unappealing.

Non-invasive ventilation (NIV) provides ventilatory support to a patientthrough the upper airways to assist the patient breathing and/ormaintain adequate oxygen levels in the body by doing some or all of thework of breathing. The ventilatory support is provided via anon-invasive patient interface. NIV has been used to treat CSR andrespiratory failure, in forms such as OHS, COPD, NMD and Chest Walldisorders. In some forms, the comfort and effectiveness of thesetherapies may be improved.

Invasive ventilation (IV) provides ventilatory support to patients thatare no longer able to effectively breathe themselves and may be providedusing a tracheostomy tube. In some forms, the comfort and effectivenessof these therapies may be improved.

2.2.3 Treatment Systems

These therapies may be provided by a treatment system or device. Suchsystems and devices may also be used to diagnose a condition withouttreating it.

A treatment system may comprise a Respiratory Pressure Therapy Device(RPT device), an air circuit, a humidifier, a patient interface, anddata management.

Another form of treatment system is a mandibular repositioning device.

2.2.3.1 Patient Interface

A patient interface may be used to interface respiratory equipment toits wearer, for example by providing a flow of air to an entrance to theairways. The flow of air may be provided via a mask to the nose and/ormouth, a tube to the mouth or a tracheostomy tube to the trachea of apatient. Depending upon the therapy to be applied, the patient interfacemay form a seal, e.g., with a region of the patient's face, tofacilitate the delivery of gas at a pressure at sufficient variance withambient pressure to effect therapy, e.g., at a positive pressure ofabout 10 cmH₂O relative to ambient pressure. For other forms of therapy,such as the delivery of oxygen, the patient interface may not include aseal sufficient to facilitate delivery to the airways of a supply of gasat a positive pressure of about 10 cmH₂O.

Certain other mask systems may be functionally unsuitable for thepresent field. For example, purely ornamental masks may be unable tomaintain a suitable pressure. Mask systems used for underwater swimmingor diving may be configured to guard against ingress of water from anexternal higher pressure, but not to maintain air internally at a higherpressure than ambient.

Certain masks may be clinically unfavourable for the present technologye.g. if they block airflow via the nose and only allow it via the mouth.

Certain masks may be uncomfortable or impractical for the presenttechnology if they require a patient to insert a portion of a maskstructure in their mouth to create and maintain a seal via their lips.

Certain masks may be impractical for use while sleeping, e.g. forsleeping while lying on one's side in bed with a head on a pillow.

The design of a patient interface presents a number of challenges. Theface has a complex three-dimensional shape. The size and shape of nosesand heads varies considerably between individuals. Since the headincludes bone, cartilage and soft tissue, different regions of the facerespond differently to mechanical forces. The jaw or mandible may moverelative to other bones of the skull. The whole head may move during thecourse of a period of respiratory therapy.

As a consequence of these challenges, some masks suffer from being oneor more of obtrusive, aesthetically undesirable, costly, poorly fitting,difficult to use, and uncomfortable especially when worn for longperiods of time or when a patient is unfamiliar with a system. Wronglysized masks can give rise to reduced compliance, reduced comfort andpoorer patient outcomes. Masks designed solely for aviators, masksdesigned as part of personal protection equipment (e.g. filter masks),SCUBA masks, or for the administration of anaesthetics may be tolerablefor their original application, but nevertheless such masks may beundesirably uncomfortable to be worn for extended periods of time, e.g.,several hours. This discomfort may lead to a reduction in patientcompliance with therapy. This is even more so if the mask is to be wornduring sleep.

CPAP therapy is highly effective to treat certain respiratory disorders,provided patients comply with therapy. If a mask is uncomfortable, ordifficult to use a patient may not comply with therapy. Since it isoften recommended that a patient regularly wash their mask, if a mask isdifficult to clean (e.g., difficult to assemble or disassemble),patients may not clean their mask and this may impact on patientcompliance.

While a mask for other applications (e.g. aviators) may not be suitablefor use in treating sleep disordered breathing, a mask designed for usein treating sleep disordered breathing may be suitable for otherapplications.

For these reasons, patient interfaces for delivery of CPAP during sleepform a distinct field.

2.2.3.1.1 Seal-Forming Portion

Patient interfaces may include a seal-forming portion. Since it is indirect contact with the patient's face, the shape and configuration ofthe seal-forming portion can have a direct impact the effectiveness andcomfort of the patient interface.

A patient interface may be partly characterised according to the designintent of where the seal-forming portion is to engage with the face inuse. In one form of patient interface, a seal-forming portion maycomprise two sub-portions to engage with respective left and rightnares. In one form of patient interface, a seal-forming portion maycomprise a single element that surrounds both nares in use. Such singleelement may be designed to for example overlay an upper lip region and anasal bridge region of a face. In one form of patient interface aseal-forming portion may comprise an element that surrounds a mouthregion in use, e.g. by forming a seal on a lower lip region of a face.In one form of patient interface, a seal-forming portion may comprise asingle element that surrounds both nares and a mouth region in use.These different types of patient interfaces may be known by a variety ofnames by their manufacturer including nasal masks, full-face masks,nasal pillows, nasal puffs and oro-nasal masks.

A seal-forming portion that may be effective in one region of apatient's face may be inappropriate in another region, e.g. because ofthe different shape, structure, variability and sensitivity regions ofthe patient's face. For example, a seal on swimming goggles thatoverlays a patient's forehead may not be appropriate to use on apatient's nose.

Certain seal-forming portions may be designed for mass manufacture suchthat one design fit and be comfortable and effective for a wide range ofdifferent face shapes and sizes. To the extent to which there is amismatch between the shape of the patient's face, and the seal-formingportion of the mass-manufactured patient interface, one or both mustadapt in order for a seal to form.

One type of seal-forming portion extends around the periphery of thepatient interface, and is intended to seal against the patient's facewhen force is applied to the patient interface with the seal-formingportion in confronting engagement with the patient's face. Theseal-forming portion may include an air or fluid filled cushion, or amoulded or formed surface of a resilient seal element made of anelastomer such as a rubber. With this type of seal-forming portion, ifthe fit is not adequate, there will be gaps between the seal-formingportion and the face, and additional force will be required to force thepatient interface against the face in order to achieve a seal.

Another type of seal-forming portion incorporates a flap seal of thinmaterial positioned about the periphery of the mask so as to provide aself-sealing action against the face of the patient when positivepressure is applied within the mask Like the previous style of sealforming portion, if the match between the face and the mask is not good,additional force may be required to achieve a seal, or the mask mayleak. Furthermore, if the shape of the seal-forming portion does notmatch that of the patient, it may crease or buckle in use, giving riseto leaks.

Another type of seal-forming portion may comprise a friction-fitelement, e.g. for insertion into a naris, however some patients findthese uncomfortable.

Another form of seal-forming portion may use adhesive to achieve a seal.Some patients may find it inconvenient to constantly apply and remove anadhesive to their face.

A range of patient interface seal-forming portion technologies aredisclosed in the following patent applications, assigned to ResMedLimited: WO 1998/004,310; WO 2006/074,513; WO 2010/135,785.

One form of nasal pillow is found in the Adam Circuit manufactured byPuritan Bennett. Another nasal pillow, or nasal puff is the subject ofU.S. Pat. No. 4,782,832 (Trimble et al.), assigned to Puritan-BennettCorporation.

ResMed Limited has manufactured the following products that incorporatenasal pillows: SWIFT™ nasal pillows mask, SWIFT™ II nasal pillows mask,SWIFT™ LT nasal pillows mask, SWIFT™ FX nasal pillows mask and MIRAGELIBERTY™ full-face mask. The following patent applications, assigned toResMed Limited, describe examples of nasal pillows masks: InternationalPatent Application WO2004/073,778 (describing amongst other thingsaspects of the ResMed Limited SWIFT™ nasal pillows), US PatentApplication 2009/0044808 (describing amongst other things aspects of theResMed Limited SWIFT™ LT nasal pillows); International PatentApplications WO 2005/063,328 and WO 2006/130,903 (describing amongstother things aspects of the ResMed Limited MIRAGE LIBERTY™ full-facemask); International Patent Application WO 2009/052,560 (describingamongst other things aspects of the ResMed Limited SWIFT™ FX nasalpillows).

2.2.3.1.2 Positioning and Stabilising

A seal-forming portion of a patient interface used for positive airpressure therapy is subject to the corresponding force of the airpressure to disrupt a seal. Thus a variety of techniques have been usedto position the seal-forming portion, and to maintain it in sealingrelation with the appropriate portion of the face.

One technique is the use of adhesives. See for example US PatentApplication Publication No. US 2010/0000534. However, the use ofadhesives may be uncomfortable for some.

Another technique is the use of one or more straps and/or stabilisingharnesses. Many such harnesses suffer from being one or more ofill-fitting, bulky, uncomfortable and awkward to use.

2.2.3.2 Respiratory Pressure Therapy (RPT) Device

Air pressure generators are known in a range of applications, e.g.industrial-scale ventilation systems. However, air pressure generatorsfor medical applications have particular requirements not fulfilled bymore generalised air pressure generators, such as the reliability, sizeand weight requirements of medical devices. In addition, even devicesdesigned for medical treatment may suffer from shortcomings, pertainingto one or more of: comfort, noise, ease of use, efficacy, size, weight,manufacturability, cost, and reliability.

An example of the special requirements of certain RPT devices isacoustic noise.

Table of noise output levels of prior RPT devices (one specimen only,measured using test method specified in ISO 3744 in CPAP mode at 10cmH₂O).

A-weighted sound Year RPT Device name pressure level dB(A) (approx.)C-Series Tango ™ 31.9 2007 C-Series Tango ™ with Humidifier 33.1 2007 S8Escape ™ II 30.5 2005 S8 Escape ™ II with H4i ™ Humidifier 31.1 2005 S9AutoSet ™ 26.5 2010 S9 AutoSet ™ with H5i Humidifier 28.6 2010

One known RPT device used for treating sleep disordered breathing is theS9 Sleep Therapy System, manufactured by ResMed Limited. Another exampleof an RPT device is a ventilator. Ventilators such as the ResMedStellar™ Series of Adult and Paediatric Ventilators may provide supportfor invasive and non-invasive non-dependent ventilation for a range ofpatients for treating a number of conditions such as but not limited toNMD, OHS and COPD.

The ResMed Elisée™ 150 ventilator and ResMed VS III™ ventilator mayprovide support for invasive and non-invasive dependent ventilationsuitable for adult or paediatric patients for treating a number ofconditions. These ventilators provide volumetric and barometricventilation modes with a single or double limb circuit. RPT devicestypically comprise a pressure generator, such as a motor-driven bloweror a compressed gas reservoir, and are configured to supply a flow ofair to the airway of a patient. In some cases, the flow of air may besupplied to the airway of the patient at positive pressure. The outletof the RPT device is connected via an air circuit to a patient interfacesuch as those described above.

The designer of a device may be presented with an infinite number ofchoices to make. Design criteria often conflict, meaning that certaindesign choices are far from routine or inevitable. Furthermore, thecomfort and efficacy of certain aspects may be highly sensitive tosmall, subtle changes in one or more parameters.

2.2.3.3 Humidifier

Delivery of a flow of air without humidification may cause drying ofairways. The use of a humidifier with an RPT device and the patientinterface produces humidified gas that minimizes drying of the nasalmucosa and increases patient airway comfort. In addition in coolerclimates, warm air applied generally to the face area in and about thepatient interface is more comfortable than cold air. A range ofartificial humidification devices and systems are known, however theymay not fulfil the specialised requirements of a medical humidifier.

Medical humidifiers are used to increase humidity and/or temperature ofthe flow of air in relation to ambient air when required, typicallywhere the patient may be asleep or resting (e.g. at a hospital). Amedical humidifier for bedside placement may be small. A medicalhumidifier may be configured to only humidify and/or heat the flow ofair delivered to the patient without humidifying and/or heating thepatient's surroundings. Room-based systems (e.g. a sauna, an airconditioner, or an evaporative cooler), for example, may also humidifyair that is breathed in by the patient, however those systems would alsohumidify and/or heat the entire room, which may cause discomfort to theoccupants. Furthermore medical humidifiers may have more stringentsafety constraints than industrial humidifiers

While a number of medical humidifiers are known, they can suffer fromone or more shortcomings. Some medical humidifiers may provideinadequate humidification, some are difficult or inconvenient to use bypatients.

2.2.3.4 Data Management

There may be clinical reasons to obtain data to determine whether thepatient prescribed with respiratory therapy has been “compliant”, e.g.that the patient has used their RPT device according to certain a“compliance rule”. One example of a compliance rule for CPAP therapy isthat a patient, in order to be deemed compliant, is required to use theRPT device for at least four hours a night for at least 21 of 30consecutive days. In order to determine a patient's compliance, aprovider of the RPT device, such as a health care provider, may manuallyobtain data describing the patient's therapy using the RPT device,calculate the usage over a predetermined time period, and compare withthe compliance rule. Once the health care provider has determined thatthe patient has used their RPT device according to the compliance rule,the health care provider may notify a third party that the patient iscompliant.

There may be other aspects of a patient's therapy that would benefitfrom communication of therapy data to a third party or external system.

Existing processes to communicate and manage such data can be one ormore of costly, time-consuming, and error-prone.

2.2.3.5 Mandibular Repositioning

A mandibular repositioning device (MRD) or mandibular advancement device(MAD) is one of the treatment options for sleep apnea and snoring. It isan adjustable oral appliance available from a dentist or other supplierthat holds the lower jaw (mandible) in a forward position during sleep.The MRD is a removable device that a patient inserts into their mouthprior to going to sleep and removes following sleep. Thus, the MRD isnot designed to be worn all of the time. The MRD may be custom made orproduced in a standard form and includes a bite impression portiondesigned to allow fitting to a patient's teeth. This mechanicalprotrusion of the lower jaw expands the space behind the tongue, putstension on the pharyngeal walls to reduce collapse of the airway anddiminishes palate vibration.

In certain examples a mandibular advancement device may comprise anupper splint that is intended to engage with or fit over teeth on theupper jaw or maxilla and a lower splint that is intended to engage withor fit over teeth on the upper jaw or mandible. The upper and lowersplints are connected together laterally via a pair of connecting rods.The pair of connecting rods are fixed symmetrically on the upper splintand on the lower splint.

In such a design the length of the connecting rods is selected such thatwhen the MRD is placed in a patient's mouth the mandible is held in anadvanced position. The length of the connecting rods may be adjusted tochange the level of protrusion of the mandible. A dentist may determinea level of protrusion for the mandible that will determine the length ofthe connecting rods.

Some MRDs are structured to push the mandible forward relative to themaxilla while other MADs, such as the ResMed Narval CC™ MRD are designedto retain the mandible in a forward position. This device also reducesor minimises dental and temporo-mandibular joint (TMJ) side effects.Thus, it is configured to minimises or prevent any movement of one ormore of the teeth.

2.2.3.6 Vent Technologies

Some forms of treatment systems may include a vent to allow the washoutof exhaled carbon dioxide. The vent may allow a flow of gas from aninterior space of a patient interface, e.g., the plenum chamber, to anexterior of the patient interface, e.g., to ambient. The vent maycomprise an orifice and gas may flow through the orifice in use of themask. Many such vents are noisy. Others may become blocked in use andthus provide insufficient washout. Some vents may be disruptive of thesleep of a bed partner 1100 of the patient 1000, e.g. through noise orfocussed airflow.

ResMed Limited has developed a number of improved mask venttechnologies. See International Patent Application Publication No. WO1998/034,665; International Patent Application Publication No. WO2000/078,381; U.S. Pat. No. 6,581,594; US Patent Application PublicationNo. US 2009/0050156; US Patent Application Publication No. 2009/0044808.

Table of noise of prior masks (ISO 17510-2:2007, 10 cmH₂O pressure at 1m)

A-weighted A-weighted sound power sound pressure Mask level dB(A) dB(A)Year Mask name type (uncertainty) (uncertainty) (approx.) Glue-on (*)nasal 50.9 42.9 1981 ResCare nasal 31.5 23.5 1993 standard (*) ResMedMirage ™ nasal 29.5 21.5 1998 (*) ResMed nasal 36 (3) 28 (3) 2000UltraMirage ™ ResMed Mirage nasal 32 (3) 24 (3) 2002 Activa ™ ResMedMirage nasal 30 (3) 22 (3) 2008 Micro ™ ResMed Mirage ™ nasal 29 (3) 22(3) 2008 SoftGel ResMed Mirage ™ nasal 26 (3) 18 (3) 2010 FX ResMedMirage nasal 37   29   2004 Swift ™ (*) pillows ResMed Mirage nasal 28(3) 20 (3) 2005 Swift ™ II pillows ResMed Mirage nasal 25 (3) 17 (3)2008 Swift ™ LT pillows ResMed AirFit nasal 21 (3) 13 (3) 2014 P10pillows ((*) one specimen only, measured using test method specified inISO 3744 in CPAP mode at 10 cmH₂O)Sound pressure values of a variety ofobjects are listed below

A-weighted sound Object pressure dB(A) Notes Vacuum cleaner: NilfiskWalter 68 ISO 3744 at Broadly Litter Hog: B+ Grade 1 m distanceConversational speech 60 1 m distance Average home 50 Quiet library 40Quiet bedroom at night 30 Background in TV studio 20

2.2.4 Diagnosis and Monitoring Systems

Polysomnography (PSG) is a conventional system for diagnosis andmonitoring of cardio-pulmonary disorders, and typically involves expertclinical staff to apply the system. PSG typically involves the placementof 15 to 20 contact sensors on a person in order to record variousbodily signals such as electroencephalography (EEG), electrocardiography(ECG), electrooculograpy (EOG), electromyography (EMG), etc. PSG forsleep disordered breathing has involved two nights of observation of apatient in a clinic, one night of pure diagnosis and a second night oftitration of treatment parameters by a clinician. PSG is thereforeexpensive and inconvenient. In particular it is unsuitable for homesleep testing.

Clinical experts may be able to diagnose or monitor patients adequatelybased on visual observation of PSG signals. However, there arecircumstances where a clinical expert may not be available, or aclinical expert may not be affordable. Different clinical experts maydisagree on a patient's condition. In addition, a given clinical expertmay apply a different standard at different times.

3 BRIEF SUMMARY OF THE TECHNOLOGY

The present technology is directed towards providing medical devicesused in the diagnosis, amelioration, treatment, or prevention ofrespiratory disorders having one or more of improved comfort, cost,efficacy, ease of use and manufacturability.

A first aspect of the present technology relates to apparatus used inthe diagnosis, amelioration, treatment or prevention of a respiratorydisorder.

Another aspect of the present technology relates to methods used in thediagnosis, amelioration, treatment or prevention of a respiratorydisorder.

An aspect of certain forms of the present technology is to providemethods and/or apparatus that improve the compliance of patients withrespiratory therapy.

An aspect of the present technology relates to a patient interfaceincluding a frame assembly including connectors operatively attachableto headgear, a cushion assembly provided to the frame assembly, thecushion assembly including a seal-forming structure structured to form aseal with the patient's nose and/or mouth, and an air delivery connectorprovided to the frame assembly, the air delivery connector operativelyconnected to an air delivery tube for supplying the air at positivepressure along an air flow path. The cushion assembly is structured toreleasably connect to the frame assembly independently of the airdelivery connector. The air delivery connector is structured toreleasably connect to the frame assembly independently of the cushionassembly.

In an example, a first seal for the air flow path may be formed betweenthe air delivery connector and the frame assembly. In an example, asecond seal may be formed between the frame assembly and the cushionassembly. In an example, the first seal comprises a dynamic diametricseal and a dynamic face seal. In an example, the second seal comprises astatic diametric seal and a static face seal. In an example, the airdelivery connector is structured to engage the cushion assembly toprovide a seal for the air flow path. In an example, the cushionassembly includes a lip seal structured to provide the seal with the airdelivery connector. In an example, the air delivery connector includesan elbow assembly. In an example, the elbow assembly is adapted toswivel relative to the frame assembly. In an example, the air deliveryconnector includes a vent adaptor connector. In an example, the airdelivery connector includes a pair of quick release spring armsstructured and arranged to releasably connect to the frame assembly. Inan example, the cushion assembly includes a shell provided to theseal-forming structure, the shell and the seal-forming structurecooperating to form a plenum chamber. In an example, the frame assemblyincludes an upper headgear connector structured to connect to upperstraps of the headgear and a lower headgear connector structured toconnect to lower straps of the headgear. In an example, the upperheadgear connector includes a pair of upper headgear connector arms,each of the arms including one or more flexible portions structured andarranged to conform to varying facial profiles. In an example, each ofthe flexible portions includes one or more slots structured to form oneor more hinges. In an example, the lower headgear connector includes apair of lower headgear connector arms, each of the lower headgearconnector arms including a magnetic connector structured to connect to amagnetic headgear clip. In an example, each of the lower headgearconnector arms comprises a slot structured to form a hinge portion. Inan example, the frame assembly includes a relatively hard shroud, andthe upper and lower headgear connectors are provided to the shroud. Inan example, the shroud includes upper and lower grooves structured toreceive respective upper and lower headgear connectors. In an example,the frame assembly is provided in one size and is structured to beselectively engageable with multiple sizes of the cushion assembly. Inan example, the frame assembly includes a lockout feature along the airflow path structured and arranged to prevent direct connection orinsertion of the air delivery tube. In an example, the lockout featurecomprises a plurality of projections structured and arranged to extendtowards the air flow path. In an example, the lockout feature comprisesa single annular projection structured and arranged to extend towardsthe air flow path. In an example, the air delivery connector includes anelbow assembly comprising a plurality of vent holes and an anti-asphyxiavalve assembly. In an example, the frame assembly is provided in the airflow path.

Another aspect of the present technology relates to a frame assembly fora patient interface including an upper headgear connector structured toconnect to upper straps of headgear. The upper headgear connectorincludes a pair of upper headgear connector arms, each of the armsincluding one or more flexible portions structured and arranged toconform to varying facial profiles.

In an example, each of the flexible portions includes one or more slotsstructured to form one or more hinges. In an example, each upperheadgear connector arm includes a first flexible portion and a secondflexible portion between the first flexible portion and an upperheadgear connection point structured to connect to a respective upperstrap. In an example, the first flexible portion includes a single slotand the second flexible portion includes a plurality of slots. In anexample, the frame assembly further comprises a lower headgear connectorstructured to connect to lower straps of headgear, the lower headgearconnector including a pair of lower headgear connector arms.

In yet another example, there is a provided a frame assembly for apatient interface, comprising an upper headgear connector structured toconnect to upper straps of headgear, the upper headgear connectorincluding a pair of upper headgear connector arms, each of the armsincluding a plurality of flexible portions structured and arranged toconform to varying facial profiles, wherein each of the flexibleportions forms a plurality of hinges.

Another aspect of the present technology relates to a patient interfaceincluding a frame assembly including connectors operatively attachableto headgear, a cushion assembly provided to the frame assembly, thecushion assembly including a seal-forming structure structured to form aseal with the patient's nose and/or mouth, and an air delivery connector(e.g., elbow assembly) provided to the frame assembly, the air deliveryconnector operatively connected to an air delivery tube for supplyingthe air at positive pressure. In an example, a first seal for the airflow path is formed between the elbow assembly and the frame assembly,and a separate second seal is formed between the frame assembly and thecushion assembly. For example, the elbow assembly is structured toestablish a hard-to-hard connection and dynamic seal with the frameassembly, and the cushion assembly is structured to establish a separatehard-to-hard connection and static seal with the frame assembly.

Another aspect of the present technology relates to a patient interfaceincluding a frame assembly including connectors operatively attachableto headgear, a cushion assembly provided to the frame assembly, thecushion assembly including a seal-forming structure structured to form aseal with the patient's nose and/or mouth, and an air delivery connector(e.g., elbow assembly) provided to the frame assembly, the air deliveryconnector operatively connected to an air delivery tube for supplyingthe air at positive pressure. In an example, the frame assembly includesa lockout feature along the opening of the air flow path that isstructured and arranged to prevent direct connection or insertion of theair delivery tube. This arrangement requires use of the elbow assemblyto interconnect the frame assembly and the air delivery tube, therebyensuring that the elbow assembly (e.g., and its vent and anti-asphyxiavalve (AAV)) are present in the system.

Another aspect of one form of the present technology is a patientinterface that is moulded or otherwise constructed with a perimetershape which is complementary to that of an intended wearer.

An aspect of one form of the present technology is a method ofmanufacturing apparatus.

An aspect of certain forms of the present technology is a medical devicethat is easy to use, e.g. by a person who does not have medicaltraining, by a person who has limited dexterity, vision or by a personwith limited experience in using this type of medical device.

An aspect of one form of the present technology is a patient interfacethat may be washed in a home of a patient, e.g., in soapy water, withoutrequiring specialised cleaning equipment.

The methods/systems/devices/apparatus described herein can provideimproved functioning in a processor, such as of a processor of aspecific purpose computer, respiratory monitor and/or a respiratorytherapy apparatus. Moreover, the methods/devices/apparatus can provideimprovements in the technological field of automated management,monitoring and/or treatment of respiratory conditions, including, forexample, sleep disordered breathing.

Of course, portions of the aspects may form sub-aspects of the presenttechnology. Also, various ones of the sub-aspects and/or aspects may becombined in various manners and also constitute additional aspects orsub-aspects of the present technology.

Other features of the technology will be apparent from consideration ofthe information contained in the following detailed description,abstract, drawings and claims.

4 BRIEF DESCRIPTION OF THE DRAWINGS

The present technology is illustrated by way of example, and not by wayof limitation, in the figures of the accompanying drawings, in whichlike reference numerals refer to similar elements including:

4.1 Treatment Systems

FIG. 1A shows a system including a patient 1000 wearing a patientinterface 3000, in the form of a nasal pillows, receiving a supply ofair at positive pressure from an RPT device 4000. Air from the RPTdevice 4000 is humidified in a humidifier 5000, and passes along an aircircuit 4170 to the patient 1000. A bed partner 1100 is also shown.

FIG. 1B shows a system including a patient 1000 wearing a patientinterface 3000, in the form of a nasal mask, receiving a supply of airat positive pressure from an RPT device 4000. Air from the RPT device ishumidified in a humidifier 5000, and passes along an air circuit 4170 tothe patient 1000.

FIG. 1C shows a system including a patient 1000 wearing a patientinterface 3000, in the form of a full-face mask, receiving a supply ofair at positive pressure from an RPT device 4000. Air from the RPTdevice is humidified in a humidifier 5000, and passes along an aircircuit 4170 to the patient 1000.

4.2 Respiratory System and Facial Anatomy

FIG. 2A shows an overview of a human respiratory system including thenasal and oral cavities, the larynx, vocal folds, oesophagus, trachea,bronchus, lung, alveolar sacs, heart and diaphragm.

FIG. 2B shows a view of a human upper airway including the nasal cavity,nasal bone, lateral nasal cartilage, greater alar cartilage, nostril,lip superior, lip inferior, larynx, hard palate, soft palate,oropharynx, tongue, epiglottis, vocal folds, oesophagus and trachea.

FIG. 2C is a front view of a face with several features of surfaceanatomy identified including the lip superior, upper vermilion, lowervermilion, lip inferior, mouth width, endocanthion, a nasal ala,nasolabial sulcus and cheilion. Also indicated are the directionssuperior, inferior, radially inward and radially outward.

FIG. 2D is a side view of a head with several features of surfaceanatomy identified including glabella, sellion, pronasale, subnasale,lip superior, lip inferior, supramenton, nasal ridge, alar crest point,otobasion superior and otobasion inferior. Also indicated are thedirections superior & inferior, and anterior & posterior.

FIG. 2E is a further side view of a head. The approximate locations ofthe Frankfort horizontal and nasolabial angle are indicated. The coronalplane is also indicated.

FIG. 2F shows a base view of a nose with several features identifiedincluding naso-labial sulcus, lip inferior, upper Vermilion, naris,subnasale, columella, pronasale, the major axis of a naris and thesagittal plane.

FIG. 2G shows a side view of the superficial features of a nose.

FIG. 2H shows subcutaneal structures of the nose, including lateralcartilage, septum cartilage, greater alar cartilage, lesser alarcartilage, sesamoid cartilage, nasal bone, epidermis, adipose tissue,frontal process of the maxilla and fibrofatty tissue.

FIG. 2I shows a medial dissection of a nose, approximately severalmillimeters from a sagittal plane, amongst other things showing theseptum cartilage and medial crus of greater alar cartilage.

FIG. 2J shows a front view of the bones of a skull including thefrontal, nasal and zygomatic bones. Nasal concha are indicated, as arethe maxilla, and mandible.

FIG. 2K shows a lateral view of a skull with the outline of the surfaceof a head, as well as several muscles. The following bones are shown:frontal, sphenoid, nasal, zygomatic, maxilla, mandible, parietal,temporal and occipital. The mental protuberance is indicated. Thefollowing muscles are shown: digastricus, masseter, sternocleidomastoidand trapezius.

FIG. 2L shows an anterolateral view of a nose.

4.3 Patient Interface

FIG. 3A shows a patient interface in the form of a nasal mask inaccordance with one form of the present technology.

FIG. 3B shows a schematic of a cross-section through a structure at apoint. An outward normal at the point is indicated. The curvature at thepoint has a positive sign, and a relatively large magnitude whencompared to the magnitude of the curvature shown in FIG. 3C.

FIG. 3C shows a schematic of a cross-section through a structure at apoint. An outward normal at the point is indicated. The curvature at thepoint has a positive sign, and a relatively small magnitude whencompared to the magnitude of the curvature shown in FIG. 3B.

FIG. 3D shows a schematic of a cross-section through a structure at apoint. An outward normal at the point is indicated. The curvature at thepoint has a value of zero.

FIG. 3E shows a schematic of a cross-section through a structure at apoint. An outward normal at the point is indicated. The curvature at thepoint has a negative sign, and a relatively small magnitude whencompared to the magnitude of the curvature shown in FIG. 3F.

FIG. 3F shows a schematic of a cross-section through a structure at apoint. An outward normal at the point is indicated. The curvature at thepoint has a negative sign, and a relatively large magnitude whencompared to the magnitude of the curvature shown in FIG. 3E.

FIG. 3G shows a cushion for a mask that includes two pillows. Anexterior surface of the cushion is indicated. An edge of the surface isindicated. Dome and saddle regions are indicated.

FIG. 3H shows a cushion for a mask. An exterior surface of the cushionis indicated. An edge of the surface is indicated. A path on the surfacebetween points A and B is indicated. A straight line distance between Aand B is indicated. Two saddle regions and a dome region are indicated.

FIG. 3I shows the surface of a structure, with a one dimensional hole inthe surface. Plane curve 301D forms the boundary of a one dimensionalhole.

FIG. 3J shows a cross-section through the structure of FIG. 3I. Surface302D that bounds a two dimensional hole in the structure of FIG. 3I isindicated.

FIG. 3K shows a perspective view of the structure of FIG. 3I, includingthe two dimensional hole and the one dimensional hole. Surface 302D thatbounds a two dimensional hole in the structure of FIG. 3I is indicated.

FIG. 3L shows a mask having an inflatable bladder as a cushion.

FIG. 3M shows a cross-section through the mask of FIG. 3L, and shows theinside surface of the bladder.

FIG. 3N illustrates a left-hand rule.

FIG. 3O illustrates a right-hand rule.

FIG. 3P shows a left ear, including a left ear helix.

FIG. 3Q shows a right ear, including a right ear helix.

FIG. 3R shows a right-hand helix.

FIG. 3S shows a view of a mask, including the sign of the torsion of thespace curve defined by the edge of the sealing membrane in differentregions of the mask.

FIG. 4 is a perspective view of a patient interface shown on a patient'shead according to an example of the present technology.

FIG. 5 is a side view of the patient interface shown in FIG. 4.

FIG. 6 is a perspective view of a patient interface according to anexample of the present technology, the patient interface being shownwith the headgear removed and arm covers for upper arms of the frameassembly removed.

FIG. 7 is a front view of the patient interface shown in FIG. 6.

FIG. 8 is a rear view of the patient interface shown in FIG. 6.

FIG. 9 is a side view of the patient interface shown in FIG. 6.

FIG. 10 is an exploded view of a patient interface according to anexample of the present technology showing the cushion assembly, frameassembly, arm covers, and elbow assembly.

FIG. 11 is an exploded view of a patient interface according to anexample of the present technology showing the cushion assembly and frameassembly removably connected with the elbow assembly removed.

FIG. 12 is an exploded view of a patient interface according to anexample of the present technology showing the frame assembly and elbowassembly removably connected with the cushion assembly removed.

FIG. 13 is a cross-sectional view of a patient interface according to anexample of the present technology.

FIG. 14 is an enlarged view of the patient interface shown in FIG. 13.

FIG. 15 is a front exploded view of a cushion assembly according to anexample of the present technology.

FIG. 16 is a rear exploded view of the cushion assembly shown in FIG.15.

FIG. 17 is a front view of the cushion assembly shown in FIG. 15.

FIG. 18 is a front perspective view of a frame assembly according to anexample of the present technology.

FIG. 19 is a rear perspective view of the frame assembly shown in FIG.18.

FIG. 20 is a side view of the frame assembly shown in FIG. 18.

FIG. 21 is a rear view of the frame assembly shown in FIG. 18.

FIG. 22 is a front view of the frame assembly shown in FIG. 18.

FIG. 23 is a cross-sectional view of the frame assembly shown in FIG.21.

FIG. 24 is a front exploded view of the frame assembly shown in FIG. 18.

FIG. 25 is a rear exploded view of the frame assembly shown in FIG. 18.

FIG. 26 is a cross-sectional view of the frame assembly shown in FIG.22.

FIG. 27 is a top view of an elbow assembly according to an example ofthe present technology.

FIG. 28 is a perspective view of the elbow assembly shown in FIG. 27.

FIG. 29 is a side view of a patient interface shown on a patient's headaccording to an example of the present technology.

FIG. 30 is a perspective view of a patient interface according to anexample of the present technology, the patient interface being shownwith the headgear removed.

FIG. 31 is a front view of the patient interface shown in FIG. 30.

FIG. 32 is a rear view of the patient interface shown in FIG. 30.

FIG. 33 is a side view of the patient interface shown in FIG. 30.

FIG. 34 is an exploded view of a patient interface according to anexample of the present technology showing the cushion assembly, frameassembly, and elbow assembly.

FIG. 35 is an exploded view of a patient interface according to anexample of the present technology showing the cushion assembly and frameassembly removably connected with the elbow assembly removed.

FIG. 36 is an exploded view of a patient interface according to anexample of the present technology showing the frame assembly and elbowassembly removably connected with the cushion assembly removed.

FIG. 37 is a cross-sectional view of a patient interface according to anexample of the present technology.

FIG. 38 is an enlarged view of the patient interface shown in FIG. 37.

FIG. 39 is a front exploded view of a cushion assembly according to anexample of the present technology.

FIG. 40 is a rear exploded view of the cushion assembly shown in FIG.39.

FIG. 41 is a front view of the cushion assembly shown in FIG. 39.

FIG. 42 is a front perspective view of a frame assembly according to anexample of the present technology.

FIG. 43 is a rear perspective view of the frame assembly shown in FIG.42.

FIG. 44 is a side view of the frame assembly shown in FIG. 42.

FIG. 45 is a rear view of the frame assembly shown in FIG. 42.

FIG. 46 is a front view of the frame assembly shown in FIG. 42.

FIG. 47 is a cross-sectional view of the frame assembly shown in FIG.46.

FIG. 48 is a front exploded view of the frame assembly shown in FIG. 42.

FIG. 49 is a rear exploded view of the frame assembly shown in FIG. 42.

FIG. 50 is a perspective view of an elbow assembly according to anexample of the present technology.

FIG. 51 is an exploded view of the elbow assembly shown in FIG. 50.

FIG. 52 is a perspective view of an elbow assembly according to anexample of the present technology.

FIG. 53 is an exploded view of the elbow assembly shown in FIG. 52.

FIGS. 54A, 54B, and 54C are rear views of small, medium, and largecushion assemblies according to an example of the present technology.

FIG. 55 is an exploded view of a patient interface according to analternative example of the present technology.

FIG. 56 is a cross-sectional view of the patient interface shown in FIG.55.

FIG. 57 is a top view of an elbow assembly according to an alternativeexample of the present technology.

FIG. 58 is a cross-sectional view showing the elbow assembly of FIG. 57attached to a patient interface according to an example of the presenttechnology.

FIG. 59 is a perspective view of a patient interface shown on apatient's head according to an example of the present technology.

FIG. 60 is a side view of the patient interface shown in FIG. 59.

FIG. 61 is a perspective view of a patient interface according to anexample of the present technology, the patient interface being shownwith headgear removed.

FIG. 62 is a perspective view of the patient interface shown in FIG. 61with arm covers for upper arms of the frame assembly removed.

FIG. 63 is a front view of the patient interface shown in FIG. 62.

FIG. 64 is a rear view of the patient interface shown in FIG. 62.

FIG. 65 is a side view of the patient interface shown in FIG. 62.

FIG. 66 is an exploded view of the patient interface shown in FIG. 61showing the cushion assembly, frame assembly, arm covers, and elbowassembly.

FIG. 67 is an exploded view of the patient interface shown in FIG. 62showing the cushion assembly and frame assembly removably connected withthe elbow assembly removed.

FIG. 68 is an exploded view of a patient interface shown in FIG. 62showing the frame assembly and elbow assembly removably connected withthe cushion assembly removed.

FIG. 69 is a cross-sectional view of the patient interface shown in FIG.63.

FIG. 70 is an enlarged view of the patient interface shown in FIG. 69.

FIG. 71 is a cross-sectional view of the patient interface shown in FIG.65.

FIG. 72 is an enlarged view of the patient interface shown in FIG. 71.

FIG. 73 is a front exploded view of a cushion assembly according to anexample of the present technology.

FIG. 74 is a rear exploded view of the cushion assembly shown in FIG.73.

FIG. 75 is a front perspective view of a frame assembly according to anexample of the present technology.

FIG. 76 is a rear perspective view of the frame assembly shown in FIG.75.

FIG. 77 is a side view of the frame assembly shown in FIG. 75.

FIG. 78 is a front view of the frame assembly shown in FIG. 75.

FIG. 79 is a rear view of the frame assembly shown in FIG. 75.

FIG. 80 is a cross-sectional view of the frame assembly shown in FIG.78.

FIG. 81 is a front exploded view of the frame assembly shown in FIG. 75.

FIG. 82 is a rear exploded view of the frame assembly shown in FIG. 75.

FIG. 83 a front perspective view of a shroud for a frame assemblyaccording to an example of the present technology.

FIG. 84 is a rear perspective view of the shroud shown in FIG. 83.

FIG. 85 is a front view of the shroud shown in FIG. 83.

FIG. 86 is a rear view of the shroud shown in FIG. 83.

FIG. 87 is front view of an upper anchor or upper arm connector for ashroud according to an example of the present technology.

FIG. 88 is an enlarged view of the shroud shown in FIG. 84.

FIG. 89A is a front view of a shroud for a frame assembly according toanother example of the present technology.

FIG. 89B is a rear view of a shroud for a frame assembly according toanother example of the present technology.

FIG. 90 is an exploded view showing connection of a lower headgearconnector arm to the shroud of a frame assembly according to an exampleof the present technology.

FIG. 91 is a cross-sectional view showing connection of a lower headgearconnector arm to the shroud of a frame assembly according to an exampleof the present technology.

FIG. 92 is a front view of a frame assembly according to another exampleof the present technology.

FIGS. 93 and 94 are exploded views of lower headgear connector arms forthe frame assembly of FIG. 92.

FIG. 95 is a rear perspective view of a lower headgear connector arm forthe frame assembly of FIG. 92.

FIG. 96 shows a manufacturing process for a lower headgear connector armaccording to an example of the present technology.

FIG. 97 shows a manufacturing process for a lower headgear connector armaccording to another example of the present technology.

FIG. 98 is an exploded view showing connection of a lower headgearconnector arm to the shroud of a frame assembly according to anotherexample of the present technology.

FIG. 99 is an exploded view showing connection of an upper headgearconnector arm to the shroud of a frame assembly according to an exampleof the present technology.

FIG. 100 is a cross-sectional view showing connection of an upperheadgear connector arm to the shroud of a frame assembly according to anexample of the present technology.

FIG. 101 is a front perspective view of a headgear clip according to anexample of the present technology.

FIG. 102 is a rear perspective view of the headgear clip shown in FIG.101.

FIG. 103 is a cross-sectional view showing connection of the headgearclip of FIG. 101 to the lower headgear connector arm of a frame assemblyaccording to an example of the present technology.

FIG. 104 is a cross-sectional view showing connection of an upper sidestrap of headgear to the upper headgear connection point of a frameassembly according to an example of the present technology.

5 DETAILED DESCRIPTION OF EXAMPLES OF THE TECHNOLOGY

Before the present technology is described in further detail, it is tobe understood that the technology is not limited to the particularexamples described herein, which may vary. It is also to be understoodthat the terminology used in this disclosure is for the purpose ofdescribing only the particular examples discussed herein, and is notintended to be limiting.

The following description is provided in relation to various exampleswhich may share one or more common characteristics and/or features. Itis to be understood that one or more features of any one example may becombinable with one or more features of another example or otherexamples. In addition, any single feature or combination of features inany of the examples may constitute a further example.

5.1 Therapy

In one form, the present technology comprises a method for treating arespiratory disorder comprising the step of applying positive pressureto the entrance of the airways of a patient 1000.

In certain examples of the present technology, a supply of air atpositive pressure is provided to the nasal passages of the patient viaone or both nares.

In certain examples of the present technology, mouth breathing islimited, restricted or prevented.

5.2 Treatment Systems

In one form, the present technology comprises an apparatus or device fortreating a respiratory disorder. The apparatus or device may comprise anRPT device 4000 for supplying pressurised air to the patient 1000 via anair circuit 4170 to a patient interface 3000, e.g., see FIGS. 1A to 1C.

5.3 Patient Interface

A non-invasive patient interface 3000 in accordance with one aspect ofthe present technology comprises the following functional aspects: aseal-forming structure 3100, a plenum chamber 3200, a positioning andstabilising structure 3300, a vent 3400, one form of connection port3600 for connection to air circuit 4170, and a forehead support 3700. Insome forms a functional aspect may be provided by one or more physicalcomponents. In some forms, one physical component may provide one ormore functional aspects. In use the seal-forming structure 3100 isarranged to surround an entrance to the airways of the patient so as tofacilitate the supply of air at positive pressure to the airways.

FIGS. 4 to 28 show a non-invasive patient interface 6000 in accordancewith one aspect of the present technology comprising a frame assembly6100, a cushion assembly 6175 including a seal-forming structure 6200,an air delivery connector (e.g., elbow assembly 6600), and a positioningand stabilising structure (e.g., headgear 6800). FIGS. 4 and 5 areexemplary views of the patient interface 6000 on a patient's head (witharm covers 6750 for upper arms 6134 of the frame assembly 6100attached), and FIGS. 6 to 10 are exemplary views of the patientinterface 6000 with the headgear 6800 and the arm covers 6750 removed.In use, one form of the seal-forming structure 6200 is arranged tosurround an entrance to the airways of the patient 1000 so as tofacilitate the supply of air at positive pressure to the airways. Theseal-forming structure 6200 (e.g., constructed of silicone) may also becommonly referred to as a cushion. In some forms, a functional aspectmay be provided by one or more physical components. In some forms, onephysical component may provide one or more functional aspects.

In one form of the present technology, the frame assembly 6100 connectsas an intermediate component to the cushion assembly 6175 and the elbowassembly 6600. That is, the cushion assembly 6175 connects to the frameassembly 6100 (via a first retention feature on the frame assembly)independently of the elbow assembly 6600 (see FIG. 11), and the elbowassembly 6600 connects to the frame assembly 6100 (via a secondretention feature on the frame assembly) independently of the cushionassembly 6175 (see FIG. 12). However, the seal for the air flow path isformed between the elbow assembly 6600 and the cushion assembly 6175,i.e., the frame assembly 6100 is not in the air flow path (e.g., seeFIGS. 13 and 14). Alternatively, a first seal for the air flow path maybe formed between the elbow assembly 6600 and the frame assembly 6100,while a separate second seal may be formed between the frame assembly6100 and the cushion assembly 6175. In this instance, the frame assembly6100 may remain in the air flow path. The retention connections of thecushion assembly 6175 and the elbow assembly 6600 to the frame assembly6100 are separate and distinct from one another and allow independentengagement/disengagement, e.g., such that the frame assembly 6100 mayremain connected to either of the cushion assembly 6175 or elbowassembly 6600 when disconnecting either of these components. Forexample, this arrangement allows the cushion assembly 6175 to bedisconnected from the frame assembly 6100 (e.g., to change cushionsizes) while maintaining connection between the frame assembly 6100 andthe elbow assembly 6600, yet maintaining the ability to disconnect theelbow assembly 6600 from the frame assembly 6100.

In the illustrated example, the seal-forming structure 6200 of thepatient interface 6000 of the present technology may be held in sealingposition in use by the headgear 6800. As illustrated in FIGS. 4 and 5,the headgear 6800 includes a pair of upper side straps 6802 and a pairof lower side straps 6804 connected to a circular crown strap 6806 thatencapsulates the crown of the patient's head. The upper side straps 6802connect to the upper headgear connector 6130 of the frame assembly 6100and the lower side straps 6804 connect to the lower headgear connector6150 of the frame assembly 6100, e.g., via headgear clips 6160. The sidestraps 6802, 6804 may include an adjustable hook and loop (Velcro™)connection mechanism, e.g., Velcro™-like hook tabs, to facilitateconnection and/or adjustment.

FIGS. 59 to 100 show a patient interface 16000 according to anotherexample of the present technology. The patient interface includes aframe assembly 16100, a cushion assembly 16175 including a seal-formingstructure 16200, an air delivery connector (e.g., elbow assembly 16600),and a positioning and stabilising structure (e.g., headgear 16800including upper side straps 16802, lower side straps 16804, and crownstrap 16806). FIGS. 59 to 61 are exemplary views of the patientinterface 16000 with arm covers 16750 for upper arms 16134 of the frameassembly 16100 attached, and FIGS. 62 to 68 are exemplary views of thepatient interface 16000 with the headgear 16800 and the arm covers 16750removed.

Similar to the example described above, the cushion assembly 16175connects to the frame assembly 16100 (via a first retention feature onthe frame assembly) independently of the elbow assembly 16600 (see FIG.67), and the elbow assembly 16600 connects to the frame assembly 16100(via a second retention feature on the frame assembly) independently ofthe cushion assembly 16175 (see FIG. 68). That is, the retentionconnections of the cushion assembly 16175 and the elbow assembly 16600to the frame assembly 16100 are separate and distinct from one anotherand allow independent engagement/disengagement.

In the example of patient interface 16000, a first seal for the air flowpath is formed between the elbow assembly 16600 and the frame assembly16100, and a separate second seal is formed between the frame assembly16100 and the cushion assembly 16175. In this example, the frameassembly 16100 is provided in the air flow path. That is, the elbowassembly 16600 is structured to establish a hard-to-hard connection anddynamic seal with the frame assembly 16100, and the cushion assembly16175 is structured to establish a separate hard-to-hard connection andstatic seal with the frame assembly 16100.

Also, in the example of patient interface 16000, the frame assembly16100 includes a lockout feature along the opening 16105 that isstructured and arranged to prevent direct connection or insertion of theair circuit 4170, e.g., air delivery tube. This arrangement requires useof the elbow assembly 16600 to interconnect the frame assembly 16100 andthe air circuit 4170, thereby ensuring that the elbow assembly 16600(and its vent and anti-asphyxia valve (AAV)) are present in the system.

In the example shown in FIGS. 4 to 28 and 59-100, the patient interfaceis a full-face/oro-nasal interface type including a seal-formingstructure 6200 structured to form a seal around the patient's nose andmouth. However, aspects of the present technology may be adapted for usewith other suitable interface types, e.g., nasal interface, nasalprongs.

For example, FIGS. 29 to 54C show a non-invasive patient interface 7000in accordance with another aspect of the present technology. In thisexample, the patient interface is a nasal interface type including aseal-forming structure 7200 structured to form a seal around thepatient's nose. The patient interface 7000 comprises a frame assembly7100, a cushion assembly 7175 including the seal-forming structure 7200,an elbow assembly 7600, and a positioning and stabilising structure(e.g., headgear 7800). Similar to the above, the cushion assembly 7175connects to the frame assembly 7100 independently of the elbow assembly7600 (e.g., see FIG. 35), and the elbow assembly 7600 connects to theframe assembly 7100 independently of the cushion assembly 7175 (e.g.,see FIG. 36). In this example, the seal for the air flow path is formedbetween the elbow assembly 7600 and the cushion assembly 7175 (e.g., seeFIGS. 37 and 38).

Frame Assembly

As best shown in FIGS. 18 to 26, the frame assembly 6100 includes ashroud or wall member 6110, an upper headgear connector 6130 provided toan upper portion of the shroud 6110, and a lower headgear connector 6150provided to a lower portion of the shroud 6110. The frame assembly 6100provides a connection between the cushion assembly 6175 and the elbowassembly 6600, and also provides a connection between the cushionassembly 6175 and the headgear 6800, e.g., either in a removable fashionor a more permanent fashion, to allow sealing forces to be transferredto the cushion assembly 6175 from the headgear 6800. In the illustratedexample, upper and lower headgear connectors 6130, 6150 provide a4-point connection to the headgear 6800.

The shroud 6110 (e.g., constructed of a relatively hard plastic materialsuch as polycarbonate) includes an opening 6105 through which the elbowassembly 6600 sealingly engages with the cushion assembly 6175 (e.g.,see FIGS. 13 and 14).

In the illustrated example, the opening 6105 is bounded by an annularflange 6115 that protrudes forwardly from an anterior or front side ofthe shroud 6110. The flange 6115 includes a rim 6117 along its free endwhich defines a circular channel 6120 structured to interface with theelbow assembly 6600.

The posterior or rear side of the shroud 6110 includes a plurality ofspring arms 6125 (e.g., 3, 4, 5, or more spring arms) spaced around theopening 6105. Each of the spring arms 6125 includes a barbed endstructured to provide a mechanical interlock, e.g., snap-fit connection,with the cushion assembly 6175.

In an alternative example, as best shown in FIGS. 75 to 100, the frameassembly 16100 includes a shroud or wall member 16110, a pair (i.e.,right and left) of upper headgear connector arms 16134 (each comprisingtwo flexible portions 16140, 16145) extending from respective sides ofan upper portion of the shroud 16110, and a pair (i.e., right and left)of lower headgear connector arms 16154 extending from respective sidesof a lower portion of the shroud 16110.

In the illustrated example, the opening 16105 of the shroud 16110 (e.g.,constructed of a relatively hard plastic material such as polycarbonate)is bounded by an outer annular flange 16115 and an inner annular flange16125.

The outer annular flange 16115 protrudes forwardly from an anterior orfront side of the shroud 16110. The flange 16115 includes a rim 16117along its free end which defines a circular channel 16120 structured tointerface with the elbow assembly 16600.

The inner annular flange 16125 protrudes rearwardly from a posterior orrear side of the shroud 16110. The flange 16125 includes a plurality oftabs or catches 16127 along its perimeter (e.g., see FIGS. 70, 76, 84,86, and 88), e.g., 2, 3, 4 or more tabs, which are structured to providea mechanical interlock, e.g., snap-fit connection, with the cushionassembly 16175 so as to releasably connect the frame assembly 16100 tothe cushion assembly 16175. In the illustrated example, the tabs 16127are provided on superior and inferior sides of the flange (i.e., northand south sides), however alternative arrangements are possible, e.g.,tabs provided on anterior and posterior sides of the flange (i.e., eastand west sides).

In addition, a radially inwardly extending ridge 16400 protrudes fromthe flange 16125 into the opening 16105. As described in more detailbelow, the ridge 16400 acts as a stop to prevent over-insertion of theelbow assembly 16600 into the frame assembly 16100. Also, the ridge16400 provides a dynamic face seal with the elbow assembly 16600.

Also, the ridge 16400 includes a plurality of projections 16405 alongits perimeter (e.g., 2, 3, 4, or more projections), which are structuredto provide a lockout feature along the opening 16105 to prevent directconnection or insertion of the air circuit 4170, e.g., air deliverytube, to the frame assembly 16100. This arrangement ensures that theelbow assembly 16600 (and its vent and anti-asphyxia valve (AAV)) isused to interconnect the frame assembly 16100 and the air circuit 4170.

In the illustrated example, the plurality of projections 16405 arestructured and arranged to have minimal or no impact on noise (from flowthrough the opening 16105), impedance to air delivery (inlet flow to thepatient), and CO₂ washout (outlet flow to the vent of the elbow assembly16100).

In the nasal interface example, e.g., see FIGS. 42 to 49, the frameassembly 7100 includes a shroud 7110 and a headgear connector 7130provided to the shroud 7110 to provide a 4-point connection to theheadgear 7800. The shroud 7110 (e.g., constructed of a relatively hardplastic material such as polycarbonate) includes an opening 7105providing an annular edge structured to engage with the elbow assembly7600. The posterior or rear side of the shroud 7110 includes a pluralityof locking tabs or spring arms 7125 (e.g., 2, 3, 4, 5, or more tabs orspring arms) spaced around the opening 7105 and structured to provide amechanical interlock, e.g., snap-fit connection, with the cushionassembly 7175.

Upper and Lower Headgear Connectors

The upper headgear connector 6130 includes a shroud connection portion6132 provided to an upper portion of the shroud 6110 and a pair (i.e.,right and left) of rigidised upper headgear connector arms 6134 (eachcomprising two flexible portions 6140, 6145) extending from respectivesides of the shroud connection portion 6132 and structured to connect torespective upper headgear straps of the headgear. The lower headgearconnector 6150 includes a shroud connection portion 6152 provided to alower portion of the shroud 6110 and a pair (i.e., right and left) oflower headgear connector arms 6154 extending from respective sides ofthe shroud connection portion 6152 and structured to connect torespective lower headgear straps of the headgear.

In the illustrated example, each upper headgear connector arm 6134includes an upper headgear connection point in the form of a slot 6135structured to receive a respective upper headgear strap 6802 of theheadgear. In the illustrated example, each lower headgear connector arm6154 includes a lower headgear connection point in the form of amagnetic connector 6155 structured to locate and connect to a magnet6162 associated with a headgear clip 6160 provided to a respective lowerheadgear strap 6804 of the headgear. However, it should be appreciatedthat the upper and lower headgear connector arms 6134, 6154 may beconnected with headgear straps of the headgear in other suitablemanners.

Each of the upper headgear connector arms 6134 is structurally rigid toresist torsion (twisting) and each includes central and peripheralflexible portions 6140, 6145 to conform to varying facial profiles. Thecentral flexible portion 6140 of each arm 6134 is positioned proximal tothe shroud 6110 and the shroud connection portion 6132. The peripheralflexible portion 6145 of each arm 6134 is positioned between the upperheadgear connection point 6135 and the central flexible portion 6140.The central flexible portion 6140 is separated from the peripheralflexible portion 6145 by a first rigid portion 6143. The peripheralflexible portion 6145 is separated from the upper headgear connectionpoint 6135 by a second rigid portion 6147.

Each upper arm 6134 extends and curves in an upwards direction betweenthe eyes and ears to avoid obstructing patient's vision, position theheadgear attachment point (e.g., slot 6135) so that the upper headgearstraps extend above and avoid the patient's ears, and provide a forcevector that extends generally parallel to the Frankfort horizontal line(e.g., see FIGS. 4 and 5).

The upper arms 6134 are also curved (orthogonal to the plane of theface) to conform to the facial profile e.g., the arms curve to generallymatch the curvature of the cheek bones and avoid load on the temple.

The upper arms 6134 are rigidised to resist deformation in order tomaintain its predetermined shape to ensure the frame assembly 6100positions the headgear attachment points in the same position and avoidtranslating headgear tension forces to compressive forces resulting inuncomfortable facial contact by the upper arms.

The upper arms 6134 are also rigidised to resist tension forces that maybe provided by the headgear straps to prevent twisting of the arms.

In an example, the upper arms are rigidised or stiffened such that thatthey maintain a preformed 3D shape (not floppy) structured to conform tothe facial profile and positions the headgear attachment points in theappropriate locations. Each upper arm maintains its preformed shape dueto its rigidity or stiffness in particular orientations. The upper armsare structured to be less resistant (less stiff or rigid) to bendinginto and away from the face to adapt varying facial widths. The upperarms are rigidised such that they do not substantially deform undertension forces applied by the headgear straps, thereby acting as anintermediary between the headgear straps and the cushion assembly toconvert the tension forces from the headgear straps to a compressiveforce applied on the seal-forming structure to provide seal andstability on the face. The upper arms are also shaped to apply theappropriate force vectors on the seal-forming structure via the shell toeffect a stable and comfortable seal. In an example, the seal-formingstructure is pulled into the face under the appropriate compressiveforce that is also in line with the Frankfort horizontal plane (that ispulled directly back into the face).

In an example, the upper arms are rigidised to provide torsionalrigidity to be resistant to deformation under twisting. The upper armsare also resistant to bending deformation vertically up and downalongside the face (i.e., remain at the correct height above the ears.However, the upper arms are also structured to provide a predeterminedlevel of deformation to allow bending (allows bending towards/away fromthe face) to adjust for varying facial width. In addition, the upperarms are resilient/elastic in this orientation to allow the upper armsto return to their original positions. This feature may also preventdiscomfort by minimising the load/force exerted by the frame assembly onthe face when the headgear straps are tightened by absorbing some ofthese tension forces due to its flexibility. In some locations, theupper arms may also provide substantially rigidity/stiffness to avoidcontact of the face, wherein the arms may act as a strut to resistbending deformation or compression into the face from headgear tension.Conversely, in other locations, the flexibility of the arms may allowthe arms to collapse under tension or compression from side load (e.g.,when a patient sleeps on their side, thereby exerting a side load on thepatient interface. The arms absorb the compressive force applied by theside load and prevent it from dislodging the seal-forming structure.This flexibility also allows for better conformation to the face, whichincreases comfort and also prevents seal instability from side load.

The central flexible portion 6140 is configured to allow the respectivearm 6134 to flex to adapt to varying facial width (between patients).For example, for wide faces, the central flexible portion 6140 allowsthe arms 6134 to flex outwardly away from one another and away from theface, and for narrow faces, the central flexible portion 6140 allows thearms 6134 to flex towards one another and towards the face. In theillustrated example, the central flexible portion 6140 of each armcomprises a single slot 6141 (on an anterior side) forming a hinge.

It should be appreciated that the slot 6141 may include other suitablearrangements and configurations to modify the location and flexibilitycharacteristics of the arm, e.g., more than one slot, slots on one orboth sides of the arm (anterior and/or posterior sides), spacing betweenslots, width, depth, orientation or angle of slot on the arm. In anexample, the slot 6141 may be filled with a flexible material. Inalternative examples, the hinge may be provided by a number of differentmethods, e.g., such as a thinner cross section or the use of a flexiblematerial joint.

The first and second rigid portions 6143, 6147 provide structuralrigidity to the arms 6134 to support its predetermined shape.

The peripheral flexible portion 6145 is configured to allow therespective arm 6134 to conform to the varying curvature or profile ofthe user's face, e.g., conform to cheek variation between patients. Forexample, the peripheral flexible portion 6145 articulates to conform tothe width and profile of the cheeks above the cheek bones of the user.In the illustrated example, the peripheral flexible portion 6145 of eacharm 6134 comprises a plurality of slots 6146 (on each side of the arm,i.e., slots on anterior and posterior sides of the arm) forming aplurality of hinges over the cheek region. The hinges allow the arms6134 to articulate and conform to micro variations of the cheek regionand distribute load on the face more evenly upon headgear tension, e.g.,when compared to a rigidiser arm without any flex.

In the illustrated example, the slots 6146 are generally parallel to oneanother, generally evenly spaced apart from one another, and includesimilar widths and depths into the thickness of the arm. However, itshould be appreciated that the slots 6146 may include other suitablearrangements and configurations to modify the location and flexibilitycharacteristics of the arm 6134, e.g., number of slots, slots on one orboth sides of the arm (anterior and/or posterior sides), spacing betweenslots, width, depth, orientation or angle of slot on the arm (e.g.,slots angled relative to one another to provide bending in differentorientations). In an example, one or more of the slots 6146 may befilled with a flexible material. In an alternative example, the hingemay be provided by a plurality of flexible sections (by material) spacedapart by rigid segments.

In alternative examples, it should be appreciated that the upperheadgear connector arms 6134 may include any suitable number of flexibleportions along its length to modify its flexibility characteristics,e.g., one, two, three or more flexible portions.

In the illustrated example, to minimise discomfort, the upper arms 6134may have a smooth and curved surface profile to distribute load andallow the arms rock over the face without a concentrated load orstabbing into the face. For example, as shown in FIG. 26, each upper arm6134 may include a generally lozenge-shaped cross-section, e.g.,generally flat but slightly dome shape on either side to increasecontact comfort.

In an example, the lower headgear connector arms 6154 are relativelymore flexible than the upper headgear connector arms 6134, e.g., thelower headgear connector arms 6154 have less resistance against torsionsuch that they may twist with the lower headgear straps of the headgear.This flexibility allows the lower arms 6154 to twist and turn with thelower headgear straps to prevent forced disconnection of the retentionfeatures under these forces, i.e., maintain connection of the lower armswith the lower headgear straps.

Each lower arm 6154 comprises the magnetic connector 6155 (e.g., encasedmagnet) structured to locate and connect to the headgear clip 6160provided to the respective lower headgear strap of the headgear. Themagnetic connector 6155 also provides a receptacle 6156, which allowsinsertion and retention of a corresponding protrusion (e.g., provided bythe magnet 6162 of the headgear clip 6160) to resist disconnection fromtension of the headgear straps. The retention allows connection to bemaintained while allowing the headgear clip 6160 to rotate relative torespective lower arm 6154. That is, the protrusion/magnet 6162 of theheadgear clip 6160 and the receptacle 6156 of the magnetic connector6155 include corresponding cylindrical shapes to allow relativerotation. The magnets are used for locating the headgear clip in correctposition for retaining engagement via engagement of theprotrusion/magnet 6162 member into the receptacle 6156.

The upper and lower arms 6134, 6154 are connected to the shroud 6110 viathe respective shroud connection portion 6132, 6152. In the illustratedexample, the upper and lower arms 6134, 6154 are permanently (e.g.,co-molded, overmolded) connected to the shroud 6110. As illustrated,each shroud connection portion 6134, 6154 includes a plurality of pins6133, 6153 that are received in respective openings 6113, 6114 providedto the shroud 6110 which form rivets to mechanically secure the upperand lower arms 6134, 6154 to the shroud 6110 after the molding process(e.g., see FIGS. 21, 24, and 25). In the illustrated example, the shroud6110 includes upper and lower grooves 6111, 6112 structured to receiverespective shroud connection portions 6132, 6152 of the upper and lowerheadgear connectors, and the openings 6113, 6114 for securing the upperand lower headgear connectors are provided within the grooves 6111, 6112(e.g., see FIGS. 24 and 25). However, it should be appreciated that theupper and lower headgear connector arms 6134, 6154 may be connected tothe shroud 6110 in other suitable manners, e.g., removable connection.

In an example, the upper arms 6134 and/or the lower arms 6154 may becovered by a textile, e.g., for aesthetics, increase perception ofsoftness/comfort. For example, FIGS. 4 and 5 show a textile arm cover orsock 6750 provided to the upper arms 6134, while FIGS. 6 to 10, forexample, show the upper arms 6134 with the arm covers 6750 removed.

The upper and lower arms may provide targeted flexibility in alternativemanners. For example, the arms may be formed by a single material with avarying cross sectional thickness for targeted flexibility, e.g.,flexible areas may be thinner to provide a living hinge, while thickenedareas will have a reduced flexibility. In another example, the arms maybe formed by two or more materials, each material having differentelastic properties/young's modulus, e.g., rigid sections may be formedin rigid materials such as polycarbonate, while each rigid section maybe joined by an intermediary flexible/soft material such as liquidsilicone rubber to provide targeted flex. In another example, the armsmay be formed in layers of different materials, e.g., the arms may beformed by at least a bendable or flexible first layer. The flexiblefirst layer may provide a substrate surface for multiple rigid portionsthat are spaced apart to form a second rigid layer. The rigid portionsmay flex relative to each other, while being supported by the firstlayer. In an example, the substrate layer in this example has therequired stretch properties to provide the required tension forces tothe patient interface. In the current example, the substrate layer hasminimal to no stretch to prevent the tension forces from being absorbedby the substrate layer.

The arms provide the required stiffness (e.g. resist torsional forces,maintain a preformed shape, etc.) for maintaining the patient interfacein the desired position. However, the arms may in some cases provide areduction in comfort due to the hardness and rigidity of the component(i.e., resistance to conforming to the face). This discomfort is due toa combination of tactile feel and resistance in conforming to facialprofile variations, which may provide an undesirable load on sensitiveportions of the face. To overcome this aspect, the arms may be coated orcovered with a softer and in some cases a less rigid material. Thematerial may act to absorb some or all of the compressive forces appliedby the arms on the user's face. Moreover, the soft and/or less rigidmaterial may act to conform to facial profile variations, thereby actingas a conforming layer. In addition, the arm may be coated or coveredwith a tactile layer may have a desirable tactile feel for directcontact with the user's face. The tactile layer may comprise a desirablefabric with enhanced tactile feel and desirable predetermined stretchcharacteristics. The arm may further comprise a compliant layercomprising a less rigid and/or soft material such as foam for absorbingthe compressive forces applied by the arm on the user's face and/orcomplying with facial variations by conforming the facial profile.

In an example, both the tactile layer and the compliant layer may bestructured or comprise materials that substantially do not alter thefunction of the arms. That is, the layers should not alter the preformedshape of the arms. Moreover, the layers should allow for the arms toflex/bend in particular orientations as defined. Thus the layers shouldbe structured or comprise selected materials to maintain the function ofthe arms. Furthermore, the layers may be permanently or semi-permanentlyfixed to the arms. Alternatively, the arms may comprise a removablelayer to cover the arms. For example, the removable layer may be atextile cover or sock. The arm may comprise a superior surface forcontact with the user's face. The superior surface may comprise a foamlayer above the rigid material, which is subsequently covered by thetactile layer. The arm may also comprise an inferior surface covered bythe tactile layer.

There are a number of ways to fix the layers to the arm. In one example,the compliant layer is a foam such as memory foam, which is glued,laminating, moulded, mechanically attached, etc. to the superior surfaceof the arm. The tactile layer is then attached to the foam compliantlayer by laminating, stitching, gluing, etc. the tactile layer to thefoam. In an example, in both cases the attachment means should notsubstantially alter the shape and rigidity of the arms. That is, theattachment means for the layers should not substantially change theflexing/bending of the arms nor change the ability of the arms tomaintain its preformed shape.

In the alternative example shown in FIGS. 75 to 100, each upper headgearconnector arm 16134 includes a shroud connection portion 16132 providedto a respective upper portion of the shroud 16110, and each lowerheadgear connector arm 16154 includes a shroud connection portion 16152provided to a respective lower portion of the shroud 16110.

In the illustrated example, each upper headgear connector arm 16134includes an upper headgear connection point in the form of a slot 16135structured to receive a respective upper headgear strap 16802 of theheadgear. As best shown in FIG. 104, the bridge or cross-bar 16136defining the slot 16135 includes a leading edge 16136A that is tapered(e.g., like a knife edge) to facilitate assembly/disassembly to theupper headgear strap 16802 of the headgear. For example, the taperedleading edge 16136A may readily slide through and between theVelcro™-like hook tab 16803 and the remainder of the upper headgearstrap 16802 to facilitate assembly/disassembly without fully releasingthe Velcro™-like hook tab 16803 from the remainder of the upper headgearstrap 16802. In the illustrated example, each lower headgear connectorarm 16154 includes a lower headgear connection point in the form of amagnetic connector 16155 structured to locate and connect to a magnetassociated with a headgear clip 16160 provided to a respective lowerheadgear strap 16804 of the headgear. However, it should be appreciatedthat the upper and lower headgear connector arms 16134, 16154 may beconnected with headgear straps of the headgear in other suitablemanners.

Similar to the upper headgear connector arms described above, each ofthe upper headgear connector arms 16134 is structurally rigid to resisttorsion (twisting) and each includes central and peripheral flexibleportions 16140, 16145 to conform to varying facial profiles. The centralflexible portion 16140 (i.e., the first flexible portion) of each arm16134 is positioned proximal to the shroud connection portion 16132. Theperipheral flexible portion 16145 (i.e., the second flexible portion) ofeach arm 16134 is positioned between the upper headgear connection point16135 and the central flexible portion 16140.

In the illustrated example, the central flexible portion 16140 of eacharm 16134 comprises a single slot 16141 (on a posterior side) forming ahinge. In the illustrated example, the peripheral flexible portion 16145of each arm 16134 comprises a plurality of slots 16146 (on each side ofthe arm, i.e., slots on anterior and/or posterior sides of the arm)forming a plurality of hinges over the cheek region.

In examples, the peripheral flexible portion 16145 of each arm need notinclude slots on the anterior or posterior sides. Instead, or inaddition, the flexible portion may include one or more interconnectingelastomeric (e.g., silicone) sections that may form a flush or smoothtransition between relatively harder plastic sections, but allowflexing, bending and/or pivoting. These can be made via insert or overmolding, where the harder plastic sections are placed in the mold andthe interconnecting sections are molded over the harder plasticsections.

Each lower headgear connector arm 16154 comprises the magnetic connector16155 (including encased magnet 16155B) structured to locate and connectto the headgear clip 16160 (including encased magnet 16162) provided tothe respective lower headgear strap of the headgear, e.g., see FIG. 103.In the illustrated example, the end of each lower arm 16154 includes amagnet receiving portion 16155A to receive and align a magnet 16155B anda cap 16155C to enclose and retain the magnet 16155B to the magnetreceiving portion 16155A. As illustrated, the magnetic connector 16155provides a protrusion which allows it to be inserted and retained withina corresponding receptacle provided by the headgear clip 16160, e.g.,see FIG. 103. The headgear clip 16160 includes a catch or retaining wall16164 that resists disconnection from tension of the headgear strapswhile allowing the headgear clip 16160 to rotate (e.g., allow for 360°rotation) relative to respective lower arm 16154. In the illustratedexample, as shown in FIGS. 101, 102, and 103, the catch or retainingwall 16164 (e.g., semi-circular cross-section or U-shape) provides amechanical retention member to mechanically engage with a semi-circularperipheral region of the connector 16155. In an example, the magneticconnector 16155 and/or the catch or retaining wall 16164 may be angledor sloped to provide an undercut to facilitate retention of the headgearclip 16160 on the magnetic connector 16155.

In an example, as shown in FIG. 96, each lower headgear connector arm16154 and magnetic connector 16155 thereof may be manufactured bymolding the cap 16155C, assembling the magnet 16155B in the cap 16155C,inserting the assembled cap/magnet in a lower arm molding tool, and thenmolding the lower arm 16154 to the cap/magnet. In an example, the cap16155C may include an orientation feature, e.g., slot 16159, tofacilitate correct orientation and alignment of the cap 16155C relativeto the lower arm 16154.

In an alternative example, as shown in FIG. 97, each lower headgearconnector arm 16154 and magnetic connector 16155 thereof may bemanufactured by molding the lower arm 16154, assembling the magnet16155B in the magnet receiving portion 16155A of the lower arm 16154,inserting the assembled lower arm/magnet in a cap molding tool, and thenovermolding the cap 16155C to the lower arm/magnet.

In the illustrated example, each lower headgear connector arm 16154comprises a single slot 16156 (on a posterior side) forming a hingeportion, e.g., see FIGS. 75 and 76. This hinging portion is structuredand arranged to accommodate for facial width variation by allowing thelower arms 16154 to flex away from the patient's face in use, e.g.,allows easy adjustment during initial fitting of the patient interfaceand allows adaption to various facial geometry without affecting seal ofthe patient interface. Also, the hinging portion allows the lower arms16154 to move or flex with corresponding headgear clips 16160 in use,e.g., to prevent inadvertent detachment of the headgear clip 16160 fromthe respective magnetic connector 16155.

The upper and lower arms 16134, 16154 are connected to the shroud 16110via the respective shroud connection portion 16132, 16152. In theillustrated example, the upper and lower arms 16134, 16154 arepermanently connected (e.g., ultrasonically welded) to the shroud 16110.

As shown in FIGS. 83 to 86, the shroud 16110 includes a pair (i.e.,right and left) of upper anchors or upper arm connectors 16450 onrespective sides of an upper portion of the shroud 16110, and a pair(i.e., right and left) of lower anchors or lower arm connectors 16460 onrespective sides of a lower portion of the shroud 16110. Each upperanchor 16450 provides an opening 16452 and each lower anchor 16460provides an opening 16462.

As shown in FIGS. 90 and 91, the shroud connection portion 16152 of eachlower arm 16154 includes a protrusion 16153 that is received in theopening 16462 of a respective lower anchor 16460. The protrusion 16153includes an opening 16153A that receives a protrusion 16158 provided toa cap 16157 which engages and interlocks the shroud connection portion16152 to the cap 16157. The shroud connection portion 16152 and the cap16157 are ultrasonically welded to mechanically secure the shroudconnection portion 16152 to the cap 16157, thereby securing the lowerarm 16154 to the lower anchor 16460.

In the illustrated example, the caps 16157 are symmetrical to facilitatemanufacturing and assembly. However, it should be appreciated that thecaps for securing the lower arms may be assymetrical. For example, FIGS.92 to 95 show an alternative arrangement in which lower arms 17154 aresecured to the shroud 17110 with respective asymmetrical caps 17157.

Similarly, as shown in FIGS. 99 and 100, the shroud connection portion16132 of each upper arm 16134 includes a protrusion 16133 that isreceived in the opening 16452 of a respective upper anchor 16450. Theprotrusion 16133 includes an opening 16133A that receives a protrusion16138 provided to a cap 16137 which engages and interlocks the shroudconnection portion 16132 to the cap 16137. The shroud connection portion16132 and the cap 16137 are ultrasonically welded to mechanically securethe shroud connection portion 16132 to the cap 16137, thereby securingthe upper arm 16134 to the upper anchor 16450

However, it should be appreciated that the upper and lower headgearconnector arms 16134, 16154 may be connected to the shroud 16110 inother suitable manners, e.g., removable connection. For example, FIG. 98illustrates a connector arm 17134 connected to an anchor 17450 via asnap joint, e.g., push through snap joint arrangement including pegsstructured to engage within respective openings with a snap fit.

In an example, the upper and/or lower anchors 16450, 16460 of the shroud16110 may be structured to enhance robustness. For example, the sharpcorners along the anchor may be eliminated to reduce stressconcentration, e.g., edges along the opening of the anchor may berounded (e.g., see FIG. 87). Also, the bridge member of the anchor maybe provided with an increased thickness to increase section strength,e.g., see bridge member 16454 of upper anchor 16450 in FIG. 87. Inaddition, ribs may be provided to arms of the anchor to increasestrength, e.g., see ribs 16456 provided to arms of upper anchor 16450 inFIG. 87.

In an example, the upper arms 16134 and/or the lower arms 16154 may becovered by a textile, e.g., for aesthetics, increase perception ofsoftness/comfort, provide comfort on the face and minimise marking. Forexample, FIGS. 59 to 61 show a textile arm cover or sock 16750 providedto the upper arms 16134, while FIGS. 62 to 65, for example, show theupper arms 16134 with the arm covers 16750 removed. The cover 16750conceals the upper arms 16134 making the outer surface smooth toincrease comfort on the face, e.g., no marking and easier to slide overthe facial surface. The cover 16750 may be optionally removable.

In an example, at least a portion of the upper arms 16134 and/or thelower arms 16154 may include dimples or a gold ball pattern, e.g., foraesthetics.

In the nasal interface example, e.g., see FIGS. 42 to 49, the headgearconnector 7130 includes a shroud connection portion 7132 connected tothe shroud 7110, a pair (i.e., right and left) of upper headgearconnector arms 7134 structured to connect to respective upper headgearstraps 7802 of the headgear 7800, a pair (i.e., right and left) of lowerheadgear connector arms 7154 structured to connect to respective lowerheadgear straps 7804 of the headgear 7800, and intermediate portions7133 to interconnect the upper and lower arms 7134, 7154 with the shroudconnection portion 7132.

In the illustrated example, each upper headgear connector arm 7134includes an upper headgear connection point in the form of a slot 7135structured to receive a respective upper headgear strap 7802 of theheadgear 7800 (see FIG. 29). In the illustrated example, each lowerheadgear connector arm 7154 includes a lower headgear connection pointin the form of a magnetic connector 7155 structured to locate andconnect to a magnet associated with a headgear clip 7160 provided to arespective lower headgear strap 7804 of the headgear 7800 (see FIG. 29).However, it should be appreciated that the upper and lower headgearconnector arms 7134, 7154 may be connected with headgear straps of theheadgear in other suitable manners.

Similar to the above example, each intermediate portion 7133 of theheadgear connector 7130 assembly includes a flexible portion 7140 toconform to varying facial profiles, e.g., accommodate facial widthvariations. In the illustrated example, the flexible portion 7140comprises a single slot (on anterior and/or posterior sides) forming ahinging section adjacent the cushion assembly.

As shown in FIGS. 48 and 49, the headgear connector 7130 may include amulti-layered configuration, e.g., layers of different materials toprovided desired flexibility.

Cushion Assembly

In one form of the present technology, the cushion assembly or cushionmodule 6175 includes a main body, chassis, or shell 6180 that isconnected or otherwise provided to the seal-forming structure or cushion6200 (see FIGS. 15 and 16). The shell 6180 may be permanently (e.g.,co-molded, overmolded) or removably (e.g., mechanical interlock)connected to the cushion 6200. In an example, the cushion 6200 isconstructed of a relatively flexible or pliable material (e.g.,silicone) and the shell 6180 is constructed of a relatively rigidmaterial (e.g., polycarbonate). The shell 6180 and the cushion 6200cooperate to form the plenum chamber 6500.

The shell 6180 includes an opening 6305 by which breathable gas isdelivered to the plenum chamber 6500. The opening 6305 is bounded by anannular flange 6310 which is adapted to be connected to the frameassembly 6100 and adapted to interface (e.g., seal) with the elbowassembly 6600 which is connected to the gas delivery tube 4180.

The shell 6180 has multiple functions. For example, it forms the plenumchamber for delivery of pressurised gases to the entrance of a patient'sairways. The shell 6180 is a rigid structure that directs a force ontothe seal-forming structure for sealing to a patients face. The force isprovided by tension forces from tightening the headgear straps. Theseforces are translated from a pair of upper and lower headgear straps tothe corresponding upper and lower arms. In an example, the upper andlower arms are provided the frame assembly, which provides the headgeartension forces to the shell 6180.

The shell 6180 also provides an outer (or anterior) surface for engagingthe inner (or posterior) surface of the shroud of the frame assembly toeffect a seal. The shell also comprises separate retention features oris otherwise structured to detachably engage to the inner surface of theframe assembly. The patient interface is modular in that a single frameassembly size is capable of connection to multiple cushion assemblysizes (e.g., small to large). Thus, the shell also detachably engages tothe frame assembly such that the frame assembly is connected into apredetermined configuration that corresponds to its respective cushionassembly size. For example, smaller cushion assemblies have an overallreduced height relative to medium or large cushion assemblies. Thus theframe assembly connects in a position relative to the cushion assemblyto position the upper headgear attachment point in their correctposition (between the eyes and ears, while providing an attachment pointwhere the upper headgear straps avoid the ears). This means that theframe assembly connects at a higher position on the shell when comparedto medium or large cushion assembly sizes. In an example, medium and/orlarge sizes may not have this requirement and connect such that theframe assembly is positioned in substantially the same position.

In the alternative example shown in FIGS. 75 to 100, the cushionassembly 16175 includes shell 16180 that is connected or otherwiseprovided to the seal-forming structure or cushion 16200 (see FIGS. 73and 74). The shell 16180 and the cushion 16200 cooperate to form theplenum chamber 16500 (e.g., see FIGS. 69 and 71). The shell 16180includes an opening 16305 by which breathable gas is delivered to theplenum chamber 16500. The opening 16305 is bounded by an annular flange16310 which is adapted to connect to the frame assembly 16100.

In the nasal interface example, e.g., see FIGS. 39 to 41, the cushionassembly 7175 includes a shell 7180 that is permanently (e.g.,co-molded, overmolded) connected to the seal-forming structure orcushion 7200. In an example, the cushion 7200 is constructed of arelatively flexible or pliable material (e.g., silicone) and the shell7180 is constructed of a relatively rigid material (e.g.,polycarbonate). The shell 7180 and the cushion 7200 cooperate to formthe plenum chamber 7500. In the illustrated example, the flexible flangeor lip seal 7250 (i.e. seal 7250 provides a seal with the elbow assembly7600) is provided in one-piece with the cushion 7200, e.g., connectingportion 7149 interconnects seal 7250 and cushion 7200 as shown in FIGS.38 and 39.

Connection Between Cushion Assembly and Frame Assembly

In one form of the present technology, the shell 6180 of the cushionassembly 6175 is repeatedly engageable with and removably disengageablefrom the shroud 6110 of the frame assembly 6100 via a mechanicalinterlock, e.g., snap-fit connection.

The cushion assembly 6175 and the frame assembly 6100 includecooperating retaining structures to connect the cushion assembly 6175 tothe frame assembly 6100. In an example, the frame assembly 6100 isreleasably connectable to the cushion assembly 6175 to facilitatereplacement and/or cleaning, and to allow alternative frame assembliesand cushion assemblies to be connected to one another. Such arrangementallows multiple seals (e.g., types and sizes) to be used with thepatient interface and therefore provide a patient interface suitable forMultiple Patient Multiple Use (MPMU) usage situations. In an alternativeexample, the frame assembly 6100 may be permanently connected orintegrally formed in one-piece with the cushion assembly 6175, e.g.,co-molded

In the illustrated example, the shell 6180 includes an opening 6305bounded by an annular flange 6310 that protrudes forwardly from theshell 6180. The flange 6310 includes a plurality of tabs or catches 6315along its perimeter (e.g., see FIGS. 15 and 17), e.g., 3, 4, 5 or moretabs, which are structured to engage or interlock with correspondingspring arms 6125 on the posterior side of the shroud 6110, e.g., with asnap-fit, to releasably connect the cushion assembly 6175 to the frameassembly 6100.

The cushion assembly 6175 also includes one or more recesses 6320 (e.g.,see FIGS. 15 and 17) along the perimeter of the flange 6310 (e.g., upperand lower recesses) structured to engage or interlock with correspondingprotrusions 6127 on the posterior side of the shroud 6110, e.g., tofacilitate alignment, prevent relative rotation.

In the illustrated example, the shell 6180 of the cushion assembly 6175and the shroud 6110 of the frame assembly 6100 are relatively rigid(e.g., both formed of a relatively hard material, e.g., such aspolycarbonate) such that engagement between the shell 6180 and theshroud 6110 provides a hard-to-hard connection. Also, the perimeter,shape, and geometry of the mating surfaces provided by the shell 6180and the shroud 6110 are predetermined to facilitate alignment andmechanical/structural engagement, e.g., clean, smooth, curved matingsurfaces. That is, the relative rigidity or stiffness of the shroud andthe shell are to maintain the preformed structure of the components. Thestiffness allows for the components to maintain their shape so that theymay be easily aligned for connection.

It should be appreciated that the cushion assembly may be connected orinterlocked with the frame assembly in other suitable manners. Forexample, these components may be connected via a clip.

In the alternative example, as best shown in FIGS. 70 and 72, the innerannular flange 16125 of the shroud 16110 extends through the opening16305 of the shell 16180, and the tabs or catches 16127 of the flange16125 engage or interlock on a posterior side of the annular flange16310 of the shell 16180 so as to releasably connect the frame assembly16100 to the cushion assembly 16175. Such connection maintains ease ofuse, provides a sealed hard to hard connection, minimizes rattling androcking movement between components, and reduces impact on stability.Also, such connection stably holds the cushion assembly 16175 inposition, while allowing the appropriate force vectors to be impartedonto the cushion assembly 16175 for seal.

Also, the frame assembly 16100 is structured to form a static diametricseal and a static face seal with the cushion assembly 16175 to minimizeand control leak. As illustrated in FIGS. 70 and 72, the shroud 16110 ofthe frame assembly 16100 includes a channel adapted to receive theflange 16310 of the cushion assembly 16175. The leading edge 16310A ofthe flange 16310 and the end wall 16112A of the channel are configuredand arranged to provide a static face seal, and the outer side 16310B ofthe flange 16310 and the side wall 16112B of the channel are configuredand arranged to provide a static diametric seal.

In the nasal interface example, e.g., see FIGS. 30 to 49, the shell 7180includes a plurality of tabs or catches 7315 along the perimeter offlange 7310, which are structured to engage or interlock withcorresponding tabs or arms 7125 on the posterior side of the shroud7110, e.g., with a snap-fit, to releasably connect the cushion assembly7175 to the frame assembly 7100.

The cushion assembly 7175 also includes one or more recesses 7320 (e.g.,see FIG. 41) along the perimeter of the flange 7310 (e.g., lower recess)structured to engage or interlock with corresponding protrusions 7127(e.g., see FIG. 43) on the posterior side of the shroud 7110, e.g., tofacilitate alignment, prevent relative rotation.

In another example, as shown in FIGS. 55 to 58, the shell of the cushionassembly 8175 may include a central aperture with an internal surfacestructured to receive an annular central flange of the frame assembly8100. The shell includes a retention feature that interlocks or connectsto a retention feature on the frame assembly. In addition, a clearanceis maintained within the aperture of the shell for a bellows structure8250 of a vent adaptor 8900 (FIGS. 55 and 56) or elbow assembly 8600(FIGS. 57 and 58) to engage with a surface 8275 of the shell to effect aface seal.

The cushion assembly 6175 and the frame assembly 6100 are structured tomaintain engagement during use and prevent any unintentional or partialdisassembly during use.

In one form of the present technology, the frame assembly 6100 isengageable with the cushion assembly 6175 by posteriorly moving theframe assembly 6100 towards the cushion assembly 6175 in a directionsubstantially parallel to the Frankfort horizontal, and the frameassembly 6100 is disengageable from the cushion assembly 6175 byanteriorly moving the frame assembly 6100 from the cushion assembly 6175in a direction substantially parallel to the Frankfort horizontal.

Elbow Assembly

As shown in FIGS. 27 and 28, the elbow assembly 6600 includes a firstend portion 6610 that is repeatedly engageable with and removablydisengageable from the shroud 6110 of the frame assembly 6100 and asecond end portion 6620 adapted to connect to the air circuit 4170,e.g., via a swivel connector 6625.

The first end portion 6610 includes a pair of resilient, quick releasepinch arms 6650, i.e., cantilevered spring arm. Each of the spring orpinch arms 6650 includes a barbed end or tab 6652 structured to providea mechanical interlock, e.g., snap-fit connection, with the flange 6115of the shroud 6110.

The first end portion 6610 includes an annular side wall 6630 structuredto extend through the frame assembly 6100 and form a seal with thecushion assembly 6175.

In the illustrated example, a vent 6700 is integrated into the first endportion 6610 to allow for the washout of exhaled air, e.g., vent exitsof the vent provided along a perimeter of the first end portion 6610.

In the alternative example, as best shown in FIGS. 59, 65, 70, and 72,the elbow assembly 16600 includes a first end portion 16610 with pincharms 16650 to releasably engage with the frame assembly 16100 and asecond end portion 16620 adapted to connect to the air circuit 4170,e.g., via a swivel connector 16625.

In this example, the first end portion 16610 includes inner and outerradial walls 16630, 16640 defining a radial channel 16645 leading to aplurality of vent holes 16700 to permit the exit of exhausted gases fromthe patient interface.

In addition, the elbow assembly 16600 is structured to house an AAVassembly including AAVs structured to allow the patient to breathethrough ports if pressurized gas is not of sufficient magnitude or notdelivered.

FIGS. 50 and 51 show the elbow assembly 7600 structured for connectionto the nasal type patient interface 7000. FIGS. 52 and 53 show analternative elbow assembly 9600 structured for connection to the nasaltype patient interface 7000.

In the illustrated examples, each side of the elbow assembly 7600, 9600includes a cantilevered push button and grooves along sides of the pushbutton that allow the push button to flex. Each push button includes atab or catch that is adapted to engage the edge of the opening 7105 ofthe frame assembly 7100 with a snap fit to releasably secure the elbowassembly 7600, 9600 to the frame assembly 7100.

As best shown in FIGS. 51 and 53, a raised portion of the button andwebbing within the grooves along sides of the button is constructed of asoft, tactile material, e.g., TPE. The raised portion provides a softtactile feel for ease of use and grip, and the webbing provides seal,soft tactile feel, and spring (clip return) force. In an example, theraised portion and webbing are overmolded to the main elbow bodyincluding the push buttons.

As shown in FIGS. 50 and 51, the elbow assembly 7600 includes a ventassembly 7700 to allow for the washout of exhaled air.

Connection Between Elbow Assembly and Frame Assembly

The elbow assembly 6600 releasably connects and retains onto the frameassembly 6100 via the pinch arms 6650, e.g., quick release snap-fit. Theflange 6115 of the shroud 6110 defines the circular channel 6120 whichis structured to receive the barbed end 6652 of the pinch arms 6650 toreleasably retain the elbow assembly 6600 to the frame assembly 6100 andform a swivel connection (e.g., see FIG. 6), e.g., allow 360° freerotation of the elbow assembly 6600 relative to the frame assembly 6100.

Because the elbow assembly 6600 connects to the frame assembly 6100independently of the cushion assembly 6175, the patient is able toremove and swap different size cushion assemblies without the need fordisconnecting the elbow assembly 6600, frame assembly 6100, andheadgear.

Similarly, in the alternative example as best shown in FIG. 72, thecircular channel 16120 of the frame assembly 16100 is structured toreceive the barbed end 16652 of the pinch arms 16650 to releasablyretain the elbow assembly 16600 to the frame assembly 16100.

Seal Between Elbow Assembly and Cushion Assembly

In an example, the cushion assembly 6175 comprises a flexible flange orlip seal 6250 to provide a seal with the elbow assembly 6600. The lipseal 6250 is provided to the flange 6310 of the shell 6180 and includesa free end that extends radially inwardly into the opening 6305. Asshown in FIGS. 13 and 14, the elbow assembly 6600 is structured tomechanically interlock with the frame assembly 6100, but is structuredand arranged to sealingly engage with sealing membrane 6250 of thecushion assembly 6175 to form a seal for the air flow path, i.e.,sealing mechanism is separate from the retention features.

As illustrated, the leading edge of the side wall 6630 of the elbowassembly 6600 forms a face seal with the lip seal 6250. This form ofengagement minimises surface area contact to reduce friction, therebyallowing a seal to form between the components while allowing the elbowassembly 6600 to swivel freely relative to the frame and cushionassemblies 6100, 6175.

In the nasal interface example, e.g., see FIGS. 37 and 38, the elbowassembly 7600 is structured to mechanically interlock with the frameassembly 7100, and the leading edge of the side wall 7630 of the elbowassembly 7600 is structured and arranged to sealingly engage with thelip seal 7250 of the cushion assembly 7175 to form a seal for the airflow path.

Seal Between Elbow Assembly and Frame Assembly

In an alternative example, the elbow assembly 16600 is structured toestablish a hard-to-hard connection and seal with the frame assembly16100. As best shown in FIG. 72, a dynamic diametric seal is formedbetween the cylindrical outer surface of the outer wall 16640 of theelbow assembly 16600 and the inner surface provided by the annularflanges 16115, 16125 of the frame assembly 16100. Also, the annularflange 16125 of the frame assembly 16100 comprises the radially inwardlyextending ridge 16400 that acts as a stop to prevent over-insertion ofthe elbow assembly 16600 into the frame assembly 16100. The surface ofthe ridge 16400 also provides a dynamic face seal with the leading edgeor surface of the outer wall 16640 of the elbow assembly 16600. Thediametric seal and the face seal provided between surfaces of the outerwall 16640 and surfaces of the annular flanges 16115, 16125/ridge 16400provide two mating surfaces of contact between the elbow assembly 16600and the frame assembly 16100, which increases the surface area ofcontact between the elbow assembly 16600 and the frame assembly 16100.The two mating surfaces are configured and arranged to minimize andcontrol leak by providing a tortuous leak path, i.e., leak path betweenthe two mating surfaces extends radially to axially from interior thepatient interface to atmosphere.

Lockout Feature

As noted above, the ridge 16400 of the frame assembly 16100 includes aplurality of projections 16405 structured to provide a lockout featureto prevent direct connection or insertion of the air circuit 4170 to theframe assembly 16100.

As best shown in FIG. 72, each projection 16405 extends to the innerwall 16630 of the elbow assembly so that the projections 16405 do notextend significantly into the inlet flow path to the patient. Inaddition, each projection 16405 includes an opening 16407 (e.g., seeFIGS. 72, 83, and 88) so the projections 16405 do not significantlyblock outlet flow to the channel 16645 leading to the vent holes 16700of the elbow assembly 16100. Thus, the plurality of projections 16405are structured and arranged to have minimal or no impact on noise (fromflow through the opening 16105), impedance to air delivery (inlet flowto the patient), and CO₂ washout (outlet flow to the vent of the elbowassembly 16100.

In an alternative example, as shown in FIG. 89A, each of the projections16405 may be provided without an opening.

In another alternative, as shown in FIG. 89B, the lockout feature may beprovided by a single annular projection 16405 that extends along theentire perimeter of the ridge 16400. As illustrated, openings 16407 areprovided along the projection 16405, e.g., so the projection 16405 doesnot significantly block outlet flow to the channel 16645 leading to thevent holes 16700.

Vent Adaptor Connector

In an alternative example, a vent adaptor connector may be provided tothe patient interface, e.g., as an alternative to the elbow assembly6600. Similar to the arrangement described above, the vent adaptorconnector may be releasably connected to the frame assembly 6100independent of the cushion assembly 6175, and may sealingly engage withthe sealing membrane 6250 of the cushion assembly 6175 to form a sealfor the air flow path.

Alternative Connection/Seal of Elbow Assembly/Vent Adaptor Connector

As aforementioned, the patient interface is connectable to both an elbowassembly and a vent adaptor connector, e.g., elbow assembly/vent adaptorconnector releasably connected to the frame assembly and sealinglyengaged with the cushion assembly.

In an alternative example, as shown in FIGS. 55 to 58, the elbowassembly 8600/vent adaptor connector 8900 includes a seal or bellowsstructure 8250 (e.g., formed of silicone) structured to engage an innersurface 8275 provided to the shell of the cushion assembly 8175. Thebellows structure is structured to move towards the inner surface of theshell when pressure is increased within the components, i.e., pressuresupported seal. The bellows structure engages with the inner surface onthe shell along the inlet opening to provide a bellows face seal.

The seal forming structures of the vent adaptor connector/elbow assemblyand the shell are separate to the retention forming features. In anexample, the frame comprises a retention feature including a resilientpair of arms adapted for insertion into corresponding grooves in thevent adaptor connector/elbow assembly. The connection is also a swivelconnection allowing the vent adaptor connector/elbow assembly to swivelrelative to the cushion assembly and frame assembly. Hence, the bellowsface seal has another advantage in that it effects a seal between thecomponents with minimal friction to allow substantial relative movementwithout breaking seal. In an example, the frame assembly is structuredsuch that it does not form part of the air delivery path to the patientbut is structured to removably retain both the cushion assembly and ventadaptor connector/elbow assembly in position. The vent adaptorconnector/elbow assembly forms a seal directly with the shell of thecushion assembly through an aperture provided in the frame assembly.

This configuration allows a user to remove the vent adaptorconnector/elbow assembly from the patient interface, without the needfor disconnecting the frame assembly from the cushion assembly, i.e.,the patient can stop therapy but leave the patient interface on theface. This configuration also allows a user to remove the cushionassembly from the frame assembly and vent adaptor connector/elbowassembly without the need for disconnecting the frame assembly from thevent adaptor connector/elbow assembly. In an example, the frame assemblyis connected to the headgear, thus the headgear can remain connected tothe frame assembly and vent adaptor connector/elbow assembly while theuser tries various cushion assembly sizes (e.g., small, medium, large)without the need to reassemble multiple components.

Modularity

In the illustrated example, the frame assembly 6100 may be provided inone size (i.e., common frame assembly), which may be selectivelyengageable with multiple sizes of cushion assemblies 6175, e.g., small,medium, and large size cushion assemblies distinguished byvolume/footprint on the patient's face. Thus, the patient has thefreedom to change cushion sizes freely without the need to replace theframe assembly 6100. In an example, regardless of size, the patientinterface provides similar locations for the headgear connectors (e.g.,based on headgear vectors and clearance with the patient's eyes) and theconnection for the elbow assembly (e.g., to optimize gas washout).

In such example, the shell of each of the different size cushionassemblies includes a connector (annular flange-type connector) that iscommon or similar for all sizes (e.g., common retention feature), whichallows the one size or common frame assembly to be connected to each ofthe different size cushion assemblies, i.e., each cushion assemblyincludes a common frame retention feature on the shell for all cushionsizes.

Similar to the above, the frame assembly 7100 of the nasal interfacetype may be provided in one size (i.e., common frame assembly), whichmay be selectively engageable with multiple sizes of cushion assemblies7175, e.g., small, medium, and large size cushion. For example, FIGS.54A, 54B, and 54C are rear views of small, medium, and large cushionassemblies 7175 according to an example of the present technology. Asillustrated, each size provides a different volume or footprint on thepatient's face.

5.3.1 Seal-Forming Structure

In one form of the present technology, a seal-forming structure providesa seal-forming surface, and may additionally provide a cushioningfunction.

A seal-forming structure in accordance with the present technology maybe constructed from a soft, flexible, resilient material such assilicone. In an alternative example, the seal-forming structure mayinclude a foam cushion including a foam seal forming portion. In suchexample, such foam cushion may be provided to a shell to allowconnection to the frame assembly 6100.

In one form, the seal-forming structure comprises a sealing flange and asupport flange. The sealing flange comprises a relatively thin memberwith a thickness of less than about 1 mm, for example about 0.25 mm toabout 0.45 mm, that extends around the perimeter of the plenum chamber.Support flange may be relatively thicker than the sealing flange. Thesupport flange is disposed between the sealing flange and the marginaledge of the plenum chamber, and extends at least part of the way aroundthe perimeter. The support flange is or includes a spring-like elementand functions to support the sealing flange from buckling in use. In usethe sealing flange can readily respond to system pressure in the plenumchamber acting on its underside to urge it into tight sealing engagementwith the face.

In one form the seal-forming portion of the non-invasive patientinterface comprises a pair of nasal puffs, or nasal pillows, each nasalpuff or nasal pillow being constructed and arranged to form a seal witha respective naris of the nose of a patient.

Nasal pillows in accordance with an aspect of the present technologyinclude: a frusto-cone, at least a portion of which forms a seal on anunderside of the patient's nose, a stalk, a flexible region on theunderside of the frusto-cone and connecting the frusto-cone to thestalk. In addition, the structure to which the nasal pillow of thepresent technology is connected includes a flexible region adjacent thebase of the stalk. The flexible regions can act in concert to facilitatea universal joint structure that is accommodating of relative movementboth displacement and angular of the frusto-cone and the structure towhich the nasal pillow is connected. For example, the frusto-cone may beaxially displaced towards the structure to which the stalk is connected.

In one form, the non-invasive patient interface comprises a seal-formingportion that forms a seal in use on an upper lip region (that is, thelip superior) of the patient's face.

In one form the non-invasive patient interface comprises a seal-formingportion that forms a seal in use on a chin-region of the patient's face.

In certain forms of the present technology, a seal-forming structure isconfigured to correspond to a particular size of head and/or shape offace. For example one form of a seal-forming structure is suitable for alarge sized head, but not a small sized head. In another example, a formof seal-forming structure is suitable for a small sized head, but not alarge sized head.

5.3.2 Plenum Chamber

The plenum chamber has a perimeter that is shaped to be complementary tothe surface contour of the face of an average person in the region wherea seal will form in use. In use, a marginal edge of the plenum chamberis positioned in close proximity to an adjacent surface of the face.Actual contact with the face is provided by the seal-forming structure.The seal-forming structure may extend in use about the entire perimeterof the plenum chamber.

5.3.3 Positioning and Stabilising Structure

The seal-forming structure of the patient interface of the presenttechnology may be held in sealing position in use by the positioning andstabilising structure.

In one form of the present technology, a positioning and stabilisingstructure is provided that is configured in a manner consistent withbeing worn by a patient while sleeping. In one example the positioningand stabilising structure has a low profile, or cross-sectionalthickness, to reduce the perceived or actual bulk of the apparatus. Inone example, the positioning and stabilising structure comprises atleast one strap having a rectangular cross-section. In one example thepositioning and stabilising structure comprises at least one flat strap.

In one form of the present technology, a positioning and stabilisingstructure 3300 comprises a strap constructed from a laminate of a fabricpatient-contacting layer, a foam inner layer and a fabric outer layer.In one form, the foam is porous to allow moisture, (e.g., sweat), topass through the strap. In one form, the fabric outer layer comprisesloop material to engage with a hook material portion.

In certain forms of the present technology, a positioning andstabilising structure comprises a strap that is extensible, e.g.resiliently extensible. For example the strap may be configured in useto be in tension, and to direct a force to draw a cushion into sealingcontact with a portion of a patient's face. In an example the strap maybe configured as a tie.

In certain forms of the present technology, a positioning andstabilising structure comprises a strap that is bendable and e.g.non-rigid. An advantage of this aspect is that the strap is morecomfortable for a patient to lie upon while the patient is sleeping.

In certain forms of the present technology, a positioning andstabilizing structure provides a retaining force configured tocorrespond to a particular size of head and/or shape of face. Forexample one form of positioning and stabilizing structure provides aretaining force suitable for a large sized head, but not a small sizedhead. In another example, a form of positioning and stabilizingstructure provides a retaining force suitable for a small sized head,but not a large sized head.

5.3.4 Vent

In one form, the patient interface includes a vent constructed andarranged to allow for the washout of exhaled gases, e.g. carbon dioxide.

One form of vent in accordance with the present technology comprises aplurality of holes, for example, about 20 to about 80 holes, or about 40to about 60 holes, or about 45 to about 55 holes.

The vent may be located in the plenum chamber. Alternatively, the ventis located in a decoupling structure, e.g., a swivel.

5.3.5 Decoupling Structure(s)

In one form the patient interface includes at least one decouplingstructure, for example, a swivel or a ball and socket.

5.3.6 Connection Port

Connection port allows for connection to the air circuit.

5.3.7 Forehead Support

In the illustrated example, the frame assembly 6100 is provided withouta forehead support.

In another form, the patient interface may include a forehead support,e.g., the frame assembly may include a forehead support.

5.3.8 Anti-Asphyxia Valve

In one form, the patient interface includes an anti-asphyxia valve.

5.3.9 Ports

In one form of the present technology, a patient interface includes oneor more ports that allow access to the volume within the plenum chamber.In one form this allows a clinician to supply supplemental oxygen. Inone form, this allows for the direct measurement of a property of gaseswithin the plenum chamber, such as the pressure.

5.4 Glossary

For the purposes of the present technology disclosure, in certain formsof the present technology, one or more of the following definitions mayapply. In other forms of the present technology, alternative definitionsmay apply.

5.4.1 General

Air: In certain forms of the present technology, air may be taken tomean atmospheric air, and in other forms of the present technology airmay be taken to mean some other combination of breathable gases, e.g.atmospheric air enriched with oxygen.

Ambient: In certain forms of the present technology, the term ambientwill be taken to mean (i) external of the treatment system or patient,and (ii) immediately surrounding the treatment system or patient.

For example, ambient humidity with respect to a humidifier may be thehumidity of air immediately surrounding the humidifier, e.g. thehumidity in the room where a patient is sleeping. Such ambient humiditymay be different to the humidity outside the room where a patient issleeping.

In another example, ambient pressure may be the pressure immediatelysurrounding or external to the body.

In certain forms, ambient (e.g., acoustic) noise may be considered to bethe background noise level in the room where a patient is located, otherthan for example, noise generated by an RPT device or emanating from amask or patient interface. Ambient noise may be generated by sourcesoutside the room.

Automatic Positive Airway Pressure (APAP) therapy: CPAP therapy in whichthe treatment pressure is automatically adjustable, e.g. from breath tobreath, between minimum and maximum limits, depending on the presence orabsence of indications of SDB events.

Continuous Positive Airway Pressure (CPAP) therapy: Respiratory pressuretherapy in which the treatment pressure is approximately constantthrough a respiratory cycle of a patient. In some forms, the pressure atthe entrance to the airways will be slightly higher during exhalation,and slightly lower during inhalation. In some forms, the pressure willvary between different respiratory cycles of the patient, for example,being increased in response to detection of indications of partial upperairway obstruction, and decreased in the absence of indications ofpartial upper airway obstruction.

Flow rate: The volume (or mass) of air delivered per unit time. Flowrate may refer to an instantaneous quantity. In some cases, a referenceto flow rate will be a reference to a scalar quantity, namely a quantityhaving magnitude only. In other cases, a reference to flow rate will bea reference to a vector quantity, namely a quantity having bothmagnitude and direction. Flow rate may be given the symbol Q. ‘Flowrate’ is sometimes shortened to simply ‘flow’.

In the example of patient respiration, a flow rate may be nominallypositive for the inspiratory portion of a breathing cycle of a patient,and hence negative for the expiratory portion of the breathing cycle ofa patient. Total flow rate, Qt, is the flow rate of air leaving the RPTdevice. Vent flow rate, Qv, is the flow rate of air leaving a vent toallow washout of exhaled gases. Leak flow rate, Ql, is the flow rate ofleak from a patient interface system or elsewhere. Respiratory flowrate, Qr, is the flow rate of air that is received into the patient'srespiratory system.

Leak: The word leak will be taken to be an unintended flow of air. Inone example, leak may occur as the result of an incomplete seal betweena mask and a patient's face. In another example leak may occur in aswivel elbow to the ambient.

Noise, conducted (acoustic): Conducted noise in the present documentrefers to noise which is carried to the patient by the pneumatic path,such as the air circuit and the patient interface as well as the airtherein. In one form, conducted noise may be quantified by measuringsound pressure levels at the end of an air circuit.

Noise, radiated (acoustic): Radiated noise in the present documentrefers to noise which is carried to the patient by the ambient air. Inone form, radiated noise may be quantified by measuring soundpower/pressure levels of the object in question according to ISO 3744.

Noise, vent (acoustic): Vent noise in the present document refers tonoise which is generated by the flow of air through any vents such asvent holes of the patient interface.

Patient: A person, whether or not they are suffering from a respiratorydisease.

Pressure: Force per unit area. Pressure may be expressed in a range ofunits, including cmH₂O, g-f/cm² and hectopascal. 1 cmH₂O is equal to 1g-f/cm² and is approximately 0.98 hectopascal. In this specification,unless otherwise stated, pressure is given in units of cmH₂O.

The pressure in the patient interface is given the symbol Pm, while thetreatment pressure, which represents a target value to be achieved bythe mask pressure Pm at the current instant of time, is given the symbolPt.

Respiratory Pressure Therapy (RPT): The application of a supply of airto an entrance to the airways at a treatment pressure that is typicallypositive with respect to atmosphere.

Ventilator: A mechanical device that provides pressure support to apatient to perform some or all of the work of breathing.

5.4.1.1 Materials

Silicone or Silicone Elastomer: A synthetic rubber. In thisspecification, a reference to silicone is a reference to liquid siliconerubber (LSR) or a compression moulded silicone rubber (CMSR). One formof commercially available LSR is SILASTIC (included in the range ofproducts sold under this trademark), manufactured by Dow Corning.Another manufacturer of LSR is Wacker. Unless otherwise specified to thecontrary, an exemplary form of LSR has a Shore A (or Type A) indentationhardness in the range of about 35 to about 45 as measured using ASTMD2240.

Polycarbonate: a typically transparent thermoplastic polymer ofBisphenol-A Carbonate.

5.4.1.2 Mechanical Properties

Resilience: Ability of a material to absorb energy when deformedelastically and to release the energy upon unloading.

‘Resilient’: Will release substantially all of the energy when unloaded.Includes e.g. certain silicones, and thermoplastic elastomers.

Hardness: The ability of a material per se to resist deformation (e.g.described by a Young's Modulus, or an indentation hardness scalemeasured on a standardised sample size).

‘Soft’ materials may include silicone or thermo-plastic elastomer (TPE),and may, e.g. readily deform under finger pressure.

‘Hard’ materials may include polycarbonate, polypropylene, steel oraluminium, and may not e.g. readily deform under finger pressure.

Stiffness (or rigidity) of a structure or component: The ability of thestructure or component to resist deformation in response to an appliedload. The load may be a force or a moment, e.g. compression, tension,bending or torsion. The structure or component may offer differentresistances in different directions.

‘Floppy’ structure or component: A structure or component that willchange shape, e.g. bend, when caused to support its own weight, within arelatively short period of time such as 1 second.

‘Rigid’ structure or component: A structure or component that will notsubstantially change shape when subject to the loads typicallyencountered in use. An example of such a use may be setting up andmaintaining a patient interface in sealing relationship with an entranceto a patient's airways, e.g. at a load of approximately 20 to 30 cmH₂Opressure.

As an example, an I-beam may comprise a different bending stiffness(resistance to a bending load) in a first direction in comparison to asecond, orthogonal direction. In another example, a structure orcomponent may be floppy in a first direction and rigid in a seconddirection.

5.4.2 Respiratory Cycle

Apnea: According to some definitions, an apnea is said to have occurredwhen flow falls below a predetermined threshold for a duration, e.g. 10seconds. An obstructive apnea will be said to have occurred when,despite patient effort, some obstruction of the airway does not allowair to flow. A central apnea will be said to have occurred when an apneais detected that is due to a reduction in breathing effort, or theabsence of breathing effort, despite the airway being patent. A mixedapnea occurs when a reduction or absence of breathing effort coincideswith an obstructed airway.

Breathing rate: The rate of spontaneous respiration of a patient,usually measured in breaths per minute.

Duty cycle: The ratio of inhalation time, Ti to total breath time, Ttot.

Effort (breathing): The work done by a spontaneously breathing personattempting to breathe.

Expiratory portion of a breathing cycle: The period from the start ofexpiratory flow to the start of inspiratory flow.

Flow limitation: Flow limitation will be taken to be the state ofaffairs in a patient's respiration where an increase in effort by thepatient does not give rise to a corresponding increase in flow. Whereflow limitation occurs during an inspiratory portion of the breathingcycle it may be described as inspiratory flow limitation. Where flowlimitation occurs during an expiratory portion of the breathing cycle itmay be described as expiratory flow limitation.

Types of flow limited inspiratory waveforms:

(i) Flattened: Having a rise followed by a relatively flat portion,followed by a fall.

(ii) M-shaped: Having two local peaks, one at the leading edge, and oneat the trailing edge, and a relatively flat portion between the twopeaks.

(iii) Chair-shaped: Having a single local peak, the peak being at theleading edge, followed by a relatively flat portion.

(iv) Reverse-chair shaped: Having a relatively flat portion followed bysingle local peak, the peak being at the trailing edge.

Hypopnea: According to some definitions, a hypopnea is taken to be areduction in flow, but not a cessation of flow. In one form, a hypopneamay be said to have occurred when there is a reduction in flow below athreshold rate for a duration. A central hypopnea will be said to haveoccurred when a hypopnea is detected that is due to a reduction inbreathing effort. In one form in adults, either of the following may beregarded as being hypopneas:

(i) a 30% reduction in patient breathing for at least 10 seconds plus anassociated 4% desaturation; or(ii) a reduction in patient breathing (but less than 50%) for at least10 seconds, with an associated desaturation of at least 3% or anarousal.

Hyperpnea: An increase in flow to a level higher than normal.

Inspiratory portion of a breathing cycle: The period from the start ofinspiratory flow to the start of expiratory flow will be taken to be theinspiratory portion of a breathing cycle.

Patency (airway): The degree of the airway being open, or the extent towhich the airway is open. A patent airway is open. Airway patency may bequantified, for example with a value of one (1) being patent, and avalue of zero (0), being closed (obstructed).

Positive End-Expiratory Pressure (PEEP): The pressure above atmospherein the lungs that exists at the end of expiration.

Peak flow rate (Qpeak): The maximum value of flow rate during theinspiratory portion of the respiratory flow waveform.

Respiratory flow rate, patient airflow rate, respiratory airflow rate(Qr): These terms may be understood to refer to the RPT device'sestimate of respiratory airflow rate, as opposed to “true respiratoryflow rate” or “true respiratory airflow rate”, which is the actualrespiratory flow rate experienced by the patient, usually expressed inlitres per minute.

Tidal volume (Vt): The volume of air inhaled or exhaled during normalbreathing, when extra effort is not applied.

(inhalation) Time (Ti): The duration of the inspiratory portion of therespiratory flow rate waveform.

(exhalation) Time (Te): The duration of the expiratory portion of therespiratory flow rate waveform.

(total) Time (Ttot): The total duration between the start of oneinspiratory portion of a respiratory flow rate waveform and the start ofthe following inspiratory portion of the respiratory flow rate waveform.

Typical recent ventilation: The value of ventilation around which recentvalues of ventilation Vent over some predetermined timescale tend tocluster, that is, a measure of the central tendency of the recent valuesof ventilation.

Upper airway obstruction (UAO): includes both partial and total upperairway obstruction. This may be associated with a state of flowlimitation, in which the flow rate increases only slightly or may evendecrease as the pressure difference across the upper airway increases(Starling resistor behaviour).

Ventilation (Vent): A measure of a rate of gas being exchanged by thepatient's respiratory system. Measures of ventilation may include one orboth of inspiratory and expiratory flow, per unit time. When expressedas a volume per minute, this quantity is often referred to as “minuteventilation”. Minute ventilation is sometimes given simply as a volume,understood to be the volume per minute.

5.4.3 Ventilation

Adaptive Servo-Ventilator (ASV): A servo-ventilator that has achangeable, rather than fixed target ventilation. The changeable targetventilation may be learned from some characteristic of the patient, forexample, a respiratory characteristic of the patient.

Backup rate: A parameter of a ventilator that establishes the minimumbreathing rate (typically in number of breaths per minute) that theventilator will deliver to the patient, if not triggered by spontaneousrespiratory effort.

Cycled: The termination of a ventilator's inspiratory phase. When aventilator delivers a breath to a spontaneously breathing patient, atthe end of the inspiratory portion of the breathing cycle, theventilator is said to be cycled to stop delivering the breath.

Expiratory positive airway pressure (EPAP): a base pressure, to which apressure varying within the breath is added to produce the desired maskpressure which the ventilator will attempt to achieve at a given time.

End expiratory pressure (EEP): Desired mask pressure which theventilator will attempt to achieve at the end of the expiratory portionof the breath. If the pressure waveform template Π(Φ) is zero-valued atthe end of expiration, i.e. Π(Φ)=0 when Φ=1, the EEP is equal to theEPAP.

Inspiratory positive airway pressure (IPAP): Maximum desired maskpressure which the ventilator will attempt to achieve during theinspiratory portion of the breath.

Pressure support: A number that is indicative of the increase inpressure during ventilator inspiration over that during ventilatorexpiration, and generally means the difference in pressure between themaximum value during inspiration and the base pressure (e.g.,PS=IPAP−EPAP). In some contexts pressure support means the differencewhich the ventilator aims to achieve, rather than what it actuallyachieves.

Servo-ventilator: A ventilator that measures patient ventilation, has atarget ventilation, and which adjusts the level of pressure support tobring the patient ventilation towards the target ventilation.

Spontaneous/Timed (S/T): A mode of a ventilator or other device thatattempts to detect the initiation of a breath of a spontaneouslybreathing patient. If however, the device is unable to detect a breathwithin a predetermined period of time, the device will automaticallyinitiate delivery of the breath.

Swing: Equivalent term to pressure support.

Triggered: When a ventilator delivers a breath of air to a spontaneouslybreathing patient, it is said to be triggered to do so at the initiationof the respiratory portion of the breathing cycle by the patient'sefforts.

Typical recent ventilation: The typical recent ventilation Vtyp is thevalue around which recent measures of ventilation over somepredetermined timescale tend to cluster. For example, a measure of thecentral tendency of the measures of ventilation over recent history maybe a suitable value of a typical recent ventilation.

5.4.4 Anatomy 5.4.4.1 Anatomy of the Face

Ala: the external outer wall or “wing” of each nostril (plural: alar)

Alare: The most lateral point on the nasal ala.

Alar curvature (or alar crest) point: The most posterior point in thecurved base line of each ala, found in the crease formed by the union ofthe ala with the cheek.

Auricle: The whole external visible part of the ear.

(nose) Bony framework: The bony framework of the nose comprises thenasal bones, the frontal process of the maxillae and the nasal part ofthe frontal bone.

(nose) Cartilaginous framework: The cartilaginous framework of the nosecomprises the septal, lateral, major and minor cartilages.

Columella: the strip of skin that separates the nares and which runsfrom the pronasale to the upper lip.

Columella angle: The angle between the line drawn through the midpointof the nostril aperture and a line drawn perpendicular to the Frankfurthorizontal while intersecting subnasale.

Frankfort horizontal plane: A line extending from the most inferiorpoint of the orbital margin to the left tragion. The tragion is thedeepest point in the notch superior to the tragus of the auricle.

Glabella: Located on the soft tissue, the most prominent point in themidsagittal plane of the forehead.

Lateral nasal cartilage: A generally triangular plate of cartilage. Itssuperior margin is attached to the nasal bone and frontal process of themaxilla, and its inferior margin is connected to the greater alarcartilage.

Lip, lower (labrale inferius):

Lip, upper (labrale superius):

Greater alar cartilage: A plate of cartilage lying below the lateralnasal cartilage. It is curved around the anterior part of the naris. Itsposterior end is connected to the frontal process of the maxilla by atough fibrous membrane containing three or four minor cartilages of theala.

Nares (Nostrils): Approximately ellipsoidal apertures forming theentrance to the nasal cavity. The singular form of nares is naris(nostril). The nares are separated by the nasal septum.

Naso-labial sulcus or Naso-labial fold: The skin fold or groove thatruns from each side of the nose to the corners of the mouth, separatingthe cheeks from the upper lip.

Naso-labial angle: The angle between the columella and the upper lip,while intersecting subnasale.

Otobasion inferior: The lowest point of attachment of the auricle to theskin of the face.

Otobasion superior: The highest point of attachment of the auricle tothe skin of the face.

Pronasale: the most protruded point or tip of the nose, which can beidentified in lateral view of the rest of the portion of the head.

Philtrum: the midline groove that runs from lower border of the nasalseptum to the top of the lip in the upper lip region.

Pogonion: Located on the soft tissue, the most anterior midpoint of thechin.

Ridge (nasal): The nasal ridge is the midline prominence of the nose,extending from the Sellion to the Pronasale.

Sagittal plane: A vertical plane that passes from anterior (front) toposterior (rear) dividing the body into right and left halves.

Sellion: Located on the soft tissue, the most concave point overlyingthe area of the frontonasal suture.

Septal cartilage (nasal): The nasal septal cartilage forms part of theseptum and divides the front part of the nasal cavity.

Subalare: The point at the lower margin of the alar base, where the alarbase joins with the skin of the superior (upper) lip.

Subnasal point: Located on the soft tissue, the point at which thecolumella merges with the upper lip in the midsagittal plane.

Supramentale: The point of greatest concavity in the midline of thelower lip between labrale inferius and soft tissue pogonion

5.4.4.2 Anatomy of the Skull

Frontal bone: The frontal bone includes a large vertical portion, thesquama frontalis, corresponding to the region known as the forehead.

Mandible: The mandible forms the lower jaw. The mental protuberance isthe bony protuberance of the jaw that forms the chin.

Maxilla: The maxilla forms the upper jaw and is located above themandible and below the orbits. The frontal process of the maxillaprojects upwards by the side of the nose, and forms part of its lateralboundary.

Nasal bones: The nasal bones are two small oblong bones, varying in sizeand form in different individuals; they are placed side by side at themiddle and upper part of the face, and form, by their junction, the“bridge” of the nose.

Nasion: The intersection of the frontal bone and the two nasal bones, adepressed area directly between the eyes and superior to the bridge ofthe nose.

Occipital bone: The occipital bone is situated at the back and lowerpart of the cranium. It includes an oval aperture, the foramen magnum,through which the cranial cavity communicates with the vertebral canal.The curved plate behind the foramen magnum is the squama occipitalis.

Orbit: The bony cavity in the skull to contain the eyeball.

Parietal bones: The parietal bones are the bones that, when joinedtogether, form the roof and sides of the cranium.

Temporal bones: The temporal bones are situated on the bases and sidesof the skull, and support that part of the face known as the temple.

Zygomatic bones: The face includes two zygomatic bones, located in theupper and lateral parts of the face and forming the prominence of thecheek.

5.4.4.3 Anatomy of the Respiratory System

Diaphragm: A sheet of muscle that extends across the bottom of the ribcage. The diaphragm separates the thoracic cavity, containing the heart,lungs and ribs, from the abdominal cavity. As the diaphragm contractsthe volume of the thoracic cavity increases and air is drawn into thelungs.

Larynx: The larynx, or voice box houses the vocal folds and connects theinferior part of the pharynx (hypopharynx) with the trachea.

Lungs: The organs of respiration in humans. The conducting zone of thelungs contains the trachea, the bronchi, the bronchioles, and theterminal bronchioles. The respiratory zone contains the respiratorybronchioles, the alveolar ducts, and the alveoli.

Nasal cavity: The nasal cavity (or nasal fossa) is a large air filledspace above and behind the nose in the middle of the face. The nasalcavity is divided in two by a vertical fin called the nasal septum. Onthe sides of the nasal cavity are three horizontal outgrowths callednasal conchae (singular “concha”) or turbinates. To the front of thenasal cavity is the nose, while the back blends, via the choanae, intothe nasopharynx.

Pharynx: The part of the throat situated immediately inferior to (below)the nasal cavity, and superior to the oesophagus and larynx. The pharynxis conventionally divided into three sections: the nasopharynx(epipharynx) (the nasal part of the pharynx), the oropharynx(mesopharynx) (the oral part of the pharynx), and the laryngopharynx(hypopharynx).

5.4.5 Patient Interface

Anti-asphyxia valve (AAV): The component or sub-assembly of a masksystem that, by opening to atmosphere in a failsafe manner, reduces therisk of excessive CO₂ rebreathing by a patient.

Elbow: An elbow is an example of a structure that directs an axis offlow of air travelling therethrough to change direction through anangle. In one form, the angle may be approximately 90 degrees. Inanother form, the angle may be more, or less than 90 degrees. The elbowmay have an approximately circular cross-section. In another form theelbow may have an oval or a rectangular cross-section. In certain formsan elbow may be rotatable with respect to a mating component, e.g. about360 degrees. In certain forms an elbow may be removable from a matingcomponent, e.g. via a snap connection. In certain forms, an elbow may beassembled to a mating component via a one-time snap during manufacture,but not removable by a patient.

Frame: Frame will be taken to mean a mask structure that bears the loadof tension between two or more points of connection with a headgear. Amask frame may be a non-airtight load bearing structure in the mask.However, some forms of mask frame may also be air-tight.

Functional Dead Space:

Headgear: Headgear will be taken to mean a form of positioning andstabilizing structure designed for use on a head. For example theheadgear may comprise a collection of one or more struts, ties andstiffeners configured to locate and retain a patient interface inposition on a patient's face for delivery of respiratory therapy. Someties are formed of a soft, flexible, elastic material such as alaminated composite of foam and fabric.

Membrane: Membrane will be taken to mean a typically thin element thathas, preferably, substantially no resistance to bending, but hasresistance to being stretched.

Plenum chamber: a mask plenum chamber will be taken to mean a portion ofa patient interface having walls at least partially enclosing a volumeof space, the volume having air therein pressurised above atmosphericpressure in use. A shell may form part of the walls of a mask plenumchamber.

Seal: May be a noun form (“a seal”) which refers to a structure, or averb form (“to seal”) which refers to the effect. Two elements may beconstructed and/or arranged to ‘seal’ or to effect ‘sealing’therebetween without requiring a separate ‘seal’ element per se.

Shell: A shell will be taken to mean a curved, relatively thin structurehaving bending, tensile and compressive stiffness. For example, a curvedstructural wall of a mask may be a shell. In some forms, a shell may befaceted. In some forms a shell may be airtight. In some forms a shellmay not be airtight.

Stiffener: A stiffener will be taken to mean a structural componentdesigned to increase the bending resistance of another component in atleast one direction.

Strut: A strut will be taken to be a structural component designed toincrease the compression resistance of another component in at least onedirection.

Swivel (noun): A subassembly of components configured to rotate about acommon axis, preferably independently, preferably under low torque. Inone form, the swivel may be constructed to rotate through an angle of atleast 360 degrees. In another form, the swivel may be constructed torotate through an angle less than 360 degrees. When used in the contextof an air delivery conduit, the sub-assembly of components preferablycomprises a matched pair of cylindrical conduits. There may be little orno leak flow of air from the swivel in use.

Tie (noun): A structure designed to resist tension.

Vent: (noun): A structure that allows a flow of air from an interior ofthe mask, or conduit, to ambient air for clinically effective washout ofexhaled gases. For example, a clinically effective washout may involve aflow rate of about 10 litres per minute to about 100 litres per minute,depending on the mask design and treatment pressure.

5.4.6 Shape of Structures

Products in accordance with the present technology may comprise one ormore three-dimensional mechanical structures, for example a mask cushionor an impeller. The three-dimensional structures may be bounded bytwo-dimensional surfaces. These surfaces may be distinguished using alabel to describe an associated surface orientation, location, function,or some other characteristic. For example a structure may comprise oneor more of an anterior surface, a posterior surface, an interior surfaceand an exterior surface. In another example, a cushion structure maycomprise a face-contacting (e.g. outer) surface, and a separatenon-face-contacting (e.g. underside or inner) surface. In anotherexample, a structure may comprise a first surface and a second surface.

To facilitate describing the shape of the three-dimensional structuresand the surfaces, we first consider a cross-section through a surface ofthe structure at a point, p. See FIG. 3B to FIG. 3F, which illustrateexamples of cross-sections at point p on a surface, and the resultingplane curves. FIGS. 3B to 3F also illustrate an outward normal vector atp. The outward normal vector at p points away from the surface. In someexamples we describe the surface from the point of view of an imaginarysmall person standing upright on the surface.

5.4.6.1 Curvature in One Dimension

The curvature of a plane curve at p may be described as having a sign(e.g. positive, negative) and a magnitude (e.g. 1/radius of a circlethat just touches the curve at p).

Positive curvature: If the curve at p turns towards the outward normal,the curvature at that point will be taken to be positive (if theimaginary small person leaves the point p they must walk uphill). SeeFIG. 3B (relatively large positive curvature compared to FIG. 3C) andFIG. 3C (relatively small positive curvature compared to FIG. 3B). Suchcurves are often referred to as concave.

Zero curvature: If the curve at p is a straight line, the curvature willbe taken to be zero (if the imaginary small person leaves the point p,they can walk on a level, neither up nor down). See FIG. 3D.

Negative curvature: If the curve at p turns away from the outwardnormal, the curvature in that direction at that point will be taken tobe negative (if the imaginary small person leaves the point p they mustwalk downhill). See FIG. 3E (relatively small negative curvaturecompared to FIG. 3F) and FIG. 3F (relatively large negative curvaturecompared to FIG. 3E). Such curves are often referred to as convex.

5.4.6.2 Curvature of Two Dimensional Surfaces

A description of the shape at a given point on a two-dimensional surfacein accordance with the present technology may include multiple normalcross-sections. The multiple cross-sections may cut the surface in aplane that includes the outward normal (a “normal plane”), and eachcross-section may be taken in a different direction. Each cross-sectionresults in a plane curve with a corresponding curvature. The differentcurvatures at that point may have the same sign, or a different sign.Each of the curvatures at that point has a magnitude, e.g. relativelysmall. The plane curves in FIGS. 3B to 3F could be examples of suchmultiple cross-sections at a particular point.

Principal curvatures and directions: The directions of the normal planeswhere the curvature of the curve takes its maximum and minimum valuesare called the principal directions. In the examples of FIG. 3B to FIG.3F, the maximum curvature occurs in FIG. 3B, and the minimum occurs inFIG. 3F, hence FIG. 3B and FIG. 3F are cross sections in the principaldirections. The principal curvatures at p are the curvatures in theprincipal directions.

Region of a surface: A connected set of points on a surface. The set ofpoints in a region may have similar characteristics, e.g. curvatures orsigns.

Saddle region: A region where at each point, the principal curvatureshave opposite signs, that is, one is positive, and the other is negative(depending on the direction to which the imaginary person turns, theymay walk uphill or downhill).

Dome region: A region where at each point the principal curvatures havethe same sign, e.g. both positive (a “concave dome”) or both negative (a“convex dome”).

Cylindrical region: A region where one principal curvature is zero (or,for example, zero within manufacturing tolerances) and the otherprincipal curvature is non-zero.

Planar region: A region of a surface where both of the principalcurvatures are zero (or, for example, zero within manufacturingtolerances).

Edge of a surface: A boundary or limit of a surface or region.

Path: In certain forms of the present technology, ‘path’ will be takento mean a path in the mathematical-topological sense, e.g. a continuousspace curve from f(0) to f(1) on a surface. In certain forms of thepresent technology, a ‘path’ may be described as a route or course,including e.g. a set of points on a surface. (The path for the imaginaryperson is where they walk on the surface, and is analogous to a gardenpath).

Path length: In certain forms of the present technology, ‘path length’will be taken to the distance along the surface from f(0) to f(1), thatis, the distance along the path on the surface. There may be more thanone path between two points on a surface and such paths may havedifferent path lengths. (The path length for the imaginary person wouldbe the distance they have to walk on the surface along the path).

Straight-line distance: The straight-line distance is the distancebetween two points on a surface, but without regard to the surface. Onplanar regions, there would be a path on the surface having the samepath length as the straight-line distance between two points on thesurface. On non-planar surfaces, there may be no paths having the samepath length as the straight-line distance between two points. (For theimaginary person, the straight-line distance would correspond to thedistance ‘as the crow flies’.)

5.4.6.3 Space Curves

Space curves: Unlike a plane curve, a space curve does not necessarilylie in any particular plane. A space curve may be considered to be aone-dimensional piece of three-dimensional space. An imaginary personwalking on a strand of the DNA helix walks along a space curve. Atypical human left ear comprises a left-hand helix, see FIG. 3P. Atypical human right ear comprises a right-hand helix, see FIG. 3Q. FIG.3R shows a right-hand helix. The edge of a structure, e.g. the edge of amembrane or impeller, may follow a space curve. In general, a spacecurve may be described by a curvature and a torsion at each point on thespace curve. Torsion is a measure of how the curve turns out of a plane.Torsion has a sign and a magnitude. The torsion at a point on a spacecurve may be characterised with reference to the tangent, normal andbinormal vectors at that point.

Tangent unit vector (or unit tangent vector): For each point on a curve,a vector at the point specifies a direction from that point, as well asa magnitude. A tangent unit vector is a unit vector pointing in the samedirection as the curve at that point. If an imaginary person were flyingalong the curve and fell off her vehicle at a particular point, thedirection of the tangent vector is the direction she would betravelling.

Unit normal vector: As the imaginary person moves along the curve, thistangent vector itself changes. The unit vector pointing in the samedirection that the tangent vector is changing is called the unitprincipal normal vector. It is perpendicular to the tangent vector.

Binormal unit vector: The binormal unit vector is perpendicular to boththe tangent vector and the principal normal vector. Its direction may bedetermined by a right-hand rule (see e.g. FIG. 3O), or alternatively bya left-hand rule (FIG. 3N).

Osculating plane: The plane containing the unit tangent vector and theunit principal normal vector. See FIGS. 3N and 3O.

Torsion of a space curve: The torsion at a point of a space curve is themagnitude of the rate of change of the binormal unit vector at thatpoint. It measures how much the curve deviates from the osculatingplane. A space curve which lies in a plane has zero torsion. A spacecurve which deviates a relatively small amount from the osculating planewill have a relatively small magnitude of torsion (e.g. a gently slopinghelical path). A space curve which deviates a relatively large amountfrom the osculating plane will have a relatively large magnitude oftorsion (e.g. a steeply sloping helical path). With reference to FIG.3R, since T2>T1, the magnitude of the torsion near the top coils of thehelix of FIG. 3R is greater than the magnitude of the torsion of thebottom coils of the helix of FIG. 3R

With reference to the right-hand rule of FIG. 3O, a space curve turningtowards the direction of the right-hand binormal may be considered ashaving a right-hand positive torsion (e.g. a right-hand helix as shownin FIG. 3R). A space curve turning away from the direction of theright-hand binormal may be considered as having a right-hand negativetorsion (e.g. a left-hand helix).

Equivalently, and with reference to a left-hand rule (see FIG. 3N), aspace curve turning towards the direction of the left-hand binormal maybe considered as having a left-hand positive torsion (e.g. a left-handhelix). Hence left-hand positive is equivalent to right-hand negative.See FIG. 3S.

5.4.6.4 Holes

A surface may have a one-dimensional hole, e.g. a hole bounded by aplane curve or by a space curve. Thin structures (e.g. a membrane) witha hole, may be described as having a one-dimensional hole. See forexample the one dimensional hole in the surface of structure shown inFIG. 3I, bounded by the plane curve 301D.

A structure may have a two-dimensional hole, e.g. a hole bounded by asurface. For example, an inflatable tyre has a two dimensional holebounded by the inside surface of the tyre. In another example, a bladderwith a cavity for air or gel could have a two-dimensional hole. See forexample the cushion of FIG. 3L and the example cross-section therethrough in FIG. 3M. In a yet another example, a conduit may comprise aone-dimension hole (e.g. at its entrance or at its exit), and atwo-dimension hole bounded by the inside surface of the conduit. Seealso the two dimensional hole through the structure shown in FIG. 3K,bounded by surface 302D.

5.5 Other Remarks

A portion of the disclosure of this patent document contains materialwhich is subject to copyright protection. The copyright owner has noobjection to the facsimile reproduction by anyone of the patent documentor the patent disclosure, as it appears in Patent Office patent files orrecords, but otherwise reserves all copyright rights whatsoever.

Unless the context clearly dictates otherwise and where a range ofvalues is provided, it is understood that each intervening value, to thetenth of the unit of the lower limit, between the upper and lower limitof that range, and any other stated or intervening value in that statedrange is encompassed within the technology. The upper and lower limitsof these intervening ranges, which may be independently included in theintervening ranges, are also encompassed within the technology, subjectto any specifically excluded limit in the stated range. Where the statedrange includes one or both of the limits, ranges excluding either orboth of those included limits are also included in the technology.

Furthermore, where a value or values are stated herein as beingimplemented as part of the technology, it is understood that such valuesmay be approximated, unless otherwise stated, and such values may beutilized to any suitable significant digit to the extent that apractical technical implementation may permit or require it.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this technology belongs. Although any methods andmaterials similar or equivalent to those described herein can also beused in the practice or testing of the present technology, a limitednumber of the exemplary methods and materials are described herein.

When a particular material is identified as being used to construct acomponent, obvious alternative materials with similar properties may beused as a substitute. Furthermore, unless specified to the contrary, anyand all components herein described are understood to be capable ofbeing manufactured and, as such, may be manufactured together orseparately.

It must be noted that as used herein and in the appended claims, thesingular forms “a”, “an”, and “the” include their plural equivalents,unless the context clearly dictates otherwise.

All publications mentioned herein are incorporated herein by referencein their entirety to disclose and describe the methods and/or materialswhich are the subject of those publications. The publications discussedherein are provided solely for their disclosure prior to the filing dateof the present application. Nothing herein is to be construed as anadmission that the present technology is not entitled to antedate suchpublication by virtue of prior invention. Further, the dates ofpublication provided may be different from the actual publication dates,which may need to be independently confirmed.

The terms “comprises” and “comprising” should be interpreted asreferring to elements, components, or steps in a non-exclusive manner,indicating that the referenced elements, components, or steps may bepresent, or utilized, or combined with other elements, components, orsteps that are not expressly referenced.

The subject headings used in the detailed description are included onlyfor the ease of reference of the reader and should not be used to limitthe subject matter found throughout the disclosure or the claims. Thesubject headings should not be used in construing the scope of theclaims or the claim limitations.

Although the technology herein has been described with reference toparticular examples, it is to be understood that these examples aremerely illustrative of the principles and applications of thetechnology. In some instances, the terminology and symbols may implyspecific details that are not required to practice the technology. Forexample, although the terms “first” and “second” may be used, unlessotherwise specified, they are not intended to indicate any order but maybe utilised to distinguish between distinct elements. Furthermore,although process steps in the methodologies may be described orillustrated in an order, such an ordering is not required. Those skilledin the art will recognize that such ordering may be modified and/oraspects thereof may be conducted concurrently or even synchronously.

It is therefore to be understood that numerous modifications may be madeto the illustrative examples and that other arrangements may be devisedwithout departing from the spirit and scope of the technology.

For example, it should be appreciated that one or more features of anyone patient interface example (e.g., patient interfaces 6000, 7000,16000) may be combinable with one or more features of another patientinterface example (e.g., patient interfaces 6000, 7000, 16000) or otherexamples related thereto. For example, one or more aspects of the frameassembly 16100 (e.g., lockout feature, headgear connector arms,connection and sealing arrangement between components) may beincorporated into the patient interfaces 6000, 7000.

Also, it should be appreciated that one or more aspects of the presenttechnology may be combinable with one or more aspects of: PCTApplication No. PCT/AU2016/050892, filed Sep. 23, 2016 and entitled“Elbow Assembly”, which claims the benefit of U.S. ProvisionalApplication No. 62/222,435, filed Sep. 23, 2015 and U.S. ProvisionalApplication No. 62/376,718, filed Aug. 18, 2016; U.S. ProvisionalApplication No. 62/377,217, filed Aug. 19, 2016 and entitled “PatientInterface with a Seal-Forming Structure having Varying Thickness”; U.S.Provisional Application No. 62/377,158, filed Aug. 19, 2016 and entitled“Patient Interface with a Seal-Forming Structure having VaryingThickness”; PCT Application No. PCT/AU2016/050893, filed Sep. 23, 2016and entitled “Vent Adaptor for a Respiratory Therapy System”, whichclaims the benefit of U.S. Provisional Application No. 62/222,604, filedSep. 23, 2015; and/or PCT Application No. PCT/AU2016/050228 filed Mar.24, 2016 and entitled “Patient Interface with Blowout Prevention forSeal-Forming Portion”, which claims the benefit of U.S. ProvisionalApplication No. 62/138,009, filed Mar. 25, 2015 and U.S. ProvisionalApplication No. 62/222,503, filed Sep. 23, 2015; each of the above-notedapplications of which is incorporated herein by reference in itsentirety.

5.6 Reference Signs List Number Feature Item

-   1000 patient-   1100 bed partner-   3000 patient interface-   3100 seal-forming structure-   3200 plenum chamber-   3300 positioning and stabilising structure-   3400 vent-   3600 connection port-   3700 forehead support-   4000 RPT device-   4170 air circuit-   5000 humidifier-   6000 patient interface-   6100 frame assembly-   6105 opening-   6110 shroud-   6111 groove-   6112 groove-   6113 openings-   6114 openings-   6115 flange-   6117 rim-   6120 channel-   6125 spring arm-   6127 protrusion-   6130 upper headgear connector-   6132 shroud connection portion-   6133 pins-   6134 upper headgear connector arm-   6135 upper headgear connection point-   6140 central flexible portion-   6141 slot-   6143 first rigid portion-   6145 peripheral flexible portion-   6146 slot-   6147 second rigid portion-   6150 lower headgear connector-   6152 shroud connection portion-   6153 pins-   6154 lower headgear connector arm-   6155 magnetic connector-   6156 receptacle-   6160 headgear clip-   6162 magnet-   6175 cushion assembly-   6180 shell-   6200 seal-forming structure-   6250 lip seal-   6305 opening-   6310 flange-   6315 catch-   6320 recess-   6500 plenum chamber-   6600 elbow assembly-   6610 first end portion-   6620 second end portion-   6625 swivel connector-   6630 side wall-   6650 pinch arm-   6652 tab-   6700 vent-   6750 arm cover-   6800 headgear-   6802 upper side strap-   6804 lower side strap-   6806 crown strap-   7000 patient interface-   7100 frame assembly-   7105 opening-   7110 shroud-   7125 spring arm-   7127 protrusion-   7130 headgear connector-   7132 shroud connection portion-   7133 intermediate portion-   7134 upper headgear connector arm-   7135 slot-   7140 flexible portion-   7149 connecting portion-   7154 lower headgear connector arm-   7155 magnetic connector-   7160 headgear clip-   7175 cushion assembly-   7180 shell-   7200 seal-forming structure-   7250 seal-   7310 flange-   7315 catch-   7320 recess-   7500 plenum chamber-   7600 elbow assembly-   7630 side wall-   7700 vent assembly-   7800 headgear-   7802 upper headgear strap-   7804 lower headgear strap-   8100 frame assembly-   8175 cushion assembly-   8250 bellows structure-   8275 surface-   8600 elbow assembly-   8900 vent adaptor connector-   9600 elbow assembly-   16000 patient interface-   16100 frame assembly-   16105 opening-   16110 shroud-   16112A end wall-   16112B side wall-   16115 outer annular flange-   16117 rim-   16120 channel-   16125 inner annular flange-   16127 tab or catch-   16132 shroud connection portion-   16133 protrusion-   16133A opening-   16134 upper headgear connector arm-   16135 upper headgear connection point-   16136 bridge-   16136A leading edge-   16137 cap-   16138 protrusion-   16140 central flexible portion-   16141 slot-   16145 peripheral flexible portion-   16146 slot-   16152 shroud connection portion-   16153 protrusion-   16153A opening-   16154 lower headgear connector arm-   16155 magnetic connector-   16155A magnet receiving portion-   16155B magnet-   16155C cover-   16156 slot-   16157 cap-   16158 protrusion-   16159 slot-   16160 headgear clip-   16162 magnet-   16164 catch-   16175 cushion assembly-   16180 shell-   16200 seal-forming structure-   16305 opening-   16310 flange-   16310A leading edge-   16310B outer side-   16400 ridge-   16405 projections-   16407 opening-   16450 upper anchor-   16452 opening-   16454 bridge member-   16456 ribs-   16460 lower anchor-   16462 opening-   16500 plenum chamber-   16600 elbow assembly-   16610 first end portion-   16620 second end portion-   16625 swivel connector-   16630 inner wall-   16640 outer wall-   16645 channel-   16650 pinch arm-   16652 barbed end-   16700 vent holes-   16750 arm cover-   16800 headgear-   16802 upper side strap-   16803 tab-   16804 lower side strap-   16806 crown strap-   17110 shroud-   17134 connector arm-   17154 lower arm-   17157 cap-   17450 anchor

1. A patient interface for sealed delivery of a flow of air at acontinuously positive pressure with respect to ambient air pressure toan entrance to a patient's airways including at least entrance of apatient's nares, wherein the patient interface is configured to maintaina therapy pressure in a range of about 4 cmH2O to about 30 cmH2O aboveambient air pressure in use, throughout a patient's respiratory cycle,while the patient is sleeping, to ameliorate sleep disordered breathing;said patient interface comprising: a frame assembly including a shroudand connectors provided to the shroud, the connectors operativelyattachable to headgear; a cushion assembly provided to the frameassembly, the cushion assembly including a shell and a seal-formingstructure provided to the shell and structured to form a seal with apatient's nose and/or mouth, the shell and the seal-forming structurecooperating to form a plenum chamber pressurizable to the therapypressure, and the shell includes a circular inlet opening structured toreceive the flow or air at the therapy pressure for breathing by thepatient; and an air delivery connector provided to the frame assembly,the air delivery connector operatively connected to an air delivery tubefor supplying the flow of air at the therapy pressure along an air flowpath to the plenum chamber, wherein the cushion assembly is structuredto releasably connect to the frame assembly independently of the airdelivery connector, wherein the shell of the cushion assembly and theshroud of the frame assembly each comprise a relatively hard materialthat is more rigid than the seal-forming structure such that engagementbetween the shell and the shroud provides a hard-to-hard connection,wherein the air delivery connector is structured to releasably connectto the frame assembly independently of the cushion assembly, wherein afirst seal for the air flow path is formed between the air deliveryconnector and the frame assembly, and a separate second seal is formedbetween the frame assembly and the cushion assembly, and wherein thefirst seal comprises a dynamic diametric seal and a dynamic face seal,and the second seal comprises a static diametric seal and a static faceseal.
 2. The patient interface according to claim 1, wherein the airdelivery connector includes an elbow assembly.
 3. The patient interfaceaccording to claim 2, wherein the elbow assembly is adapted to swivelrelative to the frame assembly.
 4. The patient interface according toclaim 1, wherein the air delivery connector includes a pair of quickrelease spring arms structured and arranged to releasably connect to theframe assembly.
 5. The patient interface according to claim 1, whereinthe frame assembly includes an upper headgear connector structured toconnect to upper straps of the headgear and a lower headgear connectorstructured to connect to lower straps of the headgear.
 6. The patientinterface according to claim 5, wherein the upper headgear connectorincludes a pair of upper headgear connector arms, each of the armsincluding one or more flexible portions structured and arranged toconform to varying facial profiles.
 7. The patient interface accordingto claim 6, wherein each of the flexible portions includes one or moreslots structured to form one or more hinges.
 8. The patient interfaceaccording to claim 5, wherein the lower headgear connector includes apair of lower headgear connector arms, each of the lower headgearconnector arms including a magnetic connector structured to connect to amagnetic headgear clip.
 9. The patient interface according to claim 8,wherein each of the lower headgear connector arms comprises a slotstructured to form a hinge portion.
 10. The patient interface accordingto claim 1, wherein the frame assembly is provided in one size and isstructured to be selectively engageable with multiple sizes of thecushion assembly.
 11. The patient interface according to claim 1,wherein the frame assembly includes a lockout feature along the air flowpath structured and arranged to prevent direct connection or insertionof the air delivery tube.
 12. The patient interface according to claim11, wherein the lockout feature comprises a plurality of projectionsstructured and arranged to extend towards the air flow path.
 13. Thepatient interface according to claim 11, wherein the lockout featurecomprises a single annular projection structured and arranged to extendtowards the air flow path.
 14. The patient interface according to claim1, wherein the air delivery connector includes an elbow assemblycomprising a plurality of vent holes and an anti-asphyxia valveassembly.
 15. The patient interface according to claim 1, wherein theframe assembly is provided in the air flow path.
 16. A treatment systemused for treatment of sleep disordered breathing, comprising: thepatient interface according to claim 1; a respiratory pressure therapy(RPT) device to supply breathable gas at positive pressure; and an airdelivery tube to pass the breathable gas from the RPT device to thepatient interface.
 17. A frame assembly for a patient interface,comprising: an upper headgear connector structured to connect to upperstraps of headgear, the upper headgear connector including a pair ofupper headgear connector arms, each of the pair of upper headgearconnector arms including one or more flexible portions structured andarranged to allow each of the pair of upper headgear connector arms toconform to varying facial profiles, wherein at least one of the one ormore flexible portions includes a slot on anterior and posterior sidesof each of the pair of upper headgear connector arms, each slotincluding a depth into a thickness of each of the pair of upper headgearconnector arms structured to form a hinge.
 18. The frame assemblyaccording to claim 17, wherein each upper headgear connector armincludes a first flexible portion and a second flexible portion betweenthe first flexible portion and an upper headgear connection pointstructured to connect to a respective upper strap.
 19. The frameassembly according to claim 18, wherein the first flexible portionincludes a single slot and the second flexible portion includes aplurality of slots.
 20. The frame assembly according to claim 17,further comprising a lower headgear connector structured to connect tolower straps of headgear, the lower headgear connector including a pairof lower headgear connector arms.
 21. A treatment system used fortreatment of sleep disordered breathing, comprising: a patient interfaceincluding the frame assembly according to claim 17; a respiratorypressure therapy (RPT) device to supply breathable gas at positivepressure; and an air delivery tube to pass the breathable gas from theRPT device to the patient interface.
 22. A frame assembly for a patientinterface, comprising: an upper headgear connector structured to connectto upper straps of headgear, the upper headgear connector including apair of upper headgear connector arms, each of the pair of upperheadgear connector arms including a plurality of flexible portionsstructured and arranged to allow each of the pair of upper headgearconnector arms to conform to varying facial profiles, wherein theplurality of flexible portions form a plurality of hinges, and at leastone of the plurality of flexible portions includes a differentconfiguration than another one of the plurality of flexible portions.23. The frame assembly according to claim 22, further comprising a lowerheadgear connector structured to connect to lower straps of headgear,the lower headgear connector including a pair of lower headgearconnector arms, each of the lower headgear connector arms including aflexible portion.